Google Assistant does not recognize traits name_synonym in italian

Question

I have an issue with the google assistant and my smart home action.

I have implemented the sync intent and this is what I get:

{
        "requestId": "15365687660984021903",
        "payload": {
                "agentUserId": <user_id>,
                "devices": [{
                        "willReportState": true,
                        "traits": ["action.devices.traits.OnOff", "action.devices.traits.Toggles", "action.devices.traits.FanSpeed", "action.devices.traits.SensorState", "action.devices.traits.HumiditySetting", "action.devices.traits.TemperatureControl", "action.devices.traits.Modes"],
                        "deviceInfo": {
                                "model": <model>,
                                "swVersion": "1.0.0",
                                "hwVersion": "1.0.0",
                                "manufacturer": <manufacturer>
                        },
                        "name": {
                                "defaultNames": [],
                                "name": "Smart Hood",
                                "nicknames": ["Cop"]
                        },
                        "attributes": {
                                "queryOnlyModes": false,
                                "availableToggles": [{
                                        "name_values": [{
                                                "name_synonym": ["Light", "Lights"],
                                                "lang": "en"
                                        }, {
                                                "lang": "it",
                                                "name_synonym": ["Luci", "Luce"]
                                        }],
                                        "name": "light"
                                }, {
                                        "name": "motor",
                                        "name_values": [{
                                                "name_synonym": ["Motor", "Fan"],
                                                "lang": "en"
                                        }, {
                                                "name_synonym": ["Motore", "Ventola"],
                                                "lang": "it"
                                        }]
                                }],
                                "commandOnlyModes": true,
                                "commandOnlyToggles": true,
                                "temperatureUnitForUX": "C",
                                "queryOnlyOnOff": false,
                                "humiditySetpointRange": {
                                        "maxPercent": 100,
                                        "minPercent": 0
                                },
                                "queryOnlyTemperatureControl": true,
                                "queryOnlyHumiditySetting": true,
                                "commandOnlyOnOff": true,
                                "commandOnlyFanSpeed": true,
                                "temperatureRange": {
                                        "minThresholdCelsius": -100,
                                        "maxThresholdCelsius": 100
                                },
                                "sensorStatesSupported": [{
                                        "descriptiveCapabilities": {
                                                "availableStates": ["good", "fair", "poor", "unknown"]
                                        },
                                        "name": "AirQuality"
                                }, {
                                        "descriptiveCapabilities": {
                                                "availableStates": ["clean", "dirty", "needs replacement", "unknown"]
                                        },
                                        "name": "FilterCleanliness"
                                }, {
                                        "descriptiveCapabilities": {
                                                "availableStates": ["good", "replace soon", "replace now", "unknown"]
                                        },
                                        "name": "FilterLifeTime",
                                        "numericCapabilities": {
                                                "rawValueUnit": "PERCENTAGE"
                                        }
                                }],
                                "availableModes": [{
                                        "name": "operatingStatus",
                                        "name_values": [{
                                                "name_synonym": ["Hood mode", "Motor Mode", "Fan Mode"],
                                                "lang": "en"
                                        }, {
                                                "name_synonym": ["Funzione", "Modalità"],
                                                "lang": "it"
                                        }],
                                        "settings": [{
                                                "setting_values": [{
                                                        "lang": "en",
                                                        "setting_synonym": ["Normal"]
                                                }, {
                                                        "lang": "it",
                                                        "setting_synonym": ["Normale"]
                                                }],
                                                "setting_name": "normal"
                                        }, {
                                                "setting_name": "auto",
                                                "setting_values": [{
                                                        "lang": "en",
                                                        "setting_synonym": ["Auto"]
                                                }, {
                                                        "lang": "it",
                                                        "setting_synonym": ["Auto", "Automatica"]
                                                }]
                                        }, {
                                                "setting_values": [{
                                                        "lang": "en",
                                                        "setting_synonym": ["Intensive", "Boost"]
                                                }, {
                                                        "setting_synonym": ["Intensiva", "Boost"],
                                                        "lang": "it"
                                                }],
                                                "setting_name": "intensive"
                                        }, {
                                                "setting_name": "24h",
                                                "setting_values": [{
                                                        "setting_synonym": ["24 hours", "h24", "24h"],
                                                        "lang": "en"
                                                }, {
                                                        "setting_synonym": ["24 ore", "h24", "24h"],
                                                        "lang": "it"
                                                }]
                                        }],
                                        "ordered": false
                                }],
                                "commandOnlyTemperatureControl": false,
                                "queryOnlyToggles": false,
                                "commandOnlyHumiditySetting": false,
                                "availableFanSpeeds": {
                                        "ordered": false,
                                        "speeds": [{
                                                "speed_values": [{
                                                        "speed_synonym": ["Low", "Slow"],
                                                        "lang": "en"
                                                }, {
                                                        "speed_synonym": ["Bassa", "Lenta"],
                                                        "lang": "it"
                                                }],
                                                "speed_name": "low"
                                        }, {
                                                "speed_values": [{
                                                        "lang": "en",
                                                        "speed_synonym": ["Medium"]
                                                }, {
                                                        "lang": "it",
                                                        "speed_synonym": ["Medio"]
                                                }],
                                                "speed_name": "medium"
                                        }, {
                                                "speed_values": [{
                                                        "lang": "en",
                                                        "speed_synonym": ["High", "Fast"]
                                                }, {
                                                        "lang": "it",
                                                        "speed_synonym": ["Alta", "Veloce"]
                                                }],
                                                "speed_name": "high"
                                        }]
                                }
                        },
                        "type": "action.devices.types.HOOD",
                        "id": <device_id>
                }]
        }
}

Until yesterday it worked perfectly.

The problem is that today the google assistant does not recognize the italian synonym but only the ones in english. But in the response it uses the italian synonym!

The issue started to happen after I choose the language in the Actions console.

what could the problem be?

Thanks for helping.