Consume Grapql mutation API in spring boot using RestTemaplate or WebClient

Question

I got confused while consuming my graphql api in spring boot. the method which is sending data to another service is;

String query = "mutation{\n" +
        "createEventLog(eventLog: " + logs + "){\n" +
        "hasError\n" +
        "}\n" +
        "}";
log.info("Query: " + query);
log.info("Query type, {}", query.getClass().getSimpleName());
auditService.sendLogsToGraphQL(query);

while the logs is;

{  
    "hasError": false,  
    "message": "hello there", 
    "sender": "khattak", 
    "payload":{ 
    "type": "string",
    "title": "Event",
    "description": "This is the description of the event log"
    },
    "serviceInfo":{
        "version": "v1",  
        "date": "Thu, 20 Jan 2022 11:24:17 GMT",
        "serverStatus": "UP",
        "serviceName": "Identity"
    }
}

while the sendLogsToGraphQL is;

public void sendLogsToGraphQL(String logs){
    try {
        restTemplate.postForEntity("http://localhost:8080/graphql",
                logs, Boolean.class);
    }catch (Exception er){
        System.out.println("error = " + er);
    }
}

After this when run the application, i get the below output. with 406 error, the full error is;

2022-01-25 17:04:43.703 INFO 19032 --- [ntContainer#0-1] c.v.AuditConsumeService.engine.Consumer : Query: mutation{
createEventLog(eventLog: {
"hasError": false,
"message": "hello there",
"sender": "khattak",
"payload":{
"type": "string",
"title": "Event",
"description": "This is the description of the event log"
},
"serviceInfo":{
"version": "v1",
"date": "Thu, 20 Jan 2022 11:24:17 GMT",
"serverStatus": "UP",
"serviceName": "Identity"
}
}){
hasError
}
}
2022-01-25 17:04:43.703 INFO 19032 --- [ntContainer#0-1] c.v.AuditConsumeService.engine.Consumer : Query type, String
error = org.springframework.web.client.HttpClientErrorException$NotAcceptable: 406 : "{"timestamp":"2022-01-25T12:04:43.786+00:00","status":406,"error":"Not Acceptable","path":"/graphql"}"

In the same way i tried with webclient but useless as;

public Mono<Object> sendLogsToGraphQL(String body) throws IOException {
    Mono<Object> block = webClient
           .post()
            .uri("http://localhost:8080/graphql")//                
              .bodyValue(BodyInserters.fromValue(body))
           .retrieve()
            .bodyToMono(Object.class);

    System.out.println("Block:: " + block);
    return block;
}

I also followed the previous asked question by Feezan khattak, but that's also not working.

Thanks for the Answer in Advance :)