Fetching error message in Mule 4 not working

Question

I run the code in debug mode and realized that external service is returning me error message below error message is coming in the path error.exception.cause.errorMessage.typedValue.value Its value is as below.

typedValue.value = {"status"":"Bad Request", "message":"Invalid data"}

I want to get the message "Invalid data" in var.

My code is as follows

output application/java 
var adminEmail = vars.adminEmail
var salesRepEmail = if (!isEmpty(vars.InitialRequest.Application.PreliminaryQuestions.SalesRepresentative.EmailAddress))
                        [vars.InitialRequest.Application.PreliminaryQuestions.SalesRepresentative.EmailAddress]
                    else
                        p('emailNotifications.nonStarterNotification.defaultEmail') splitBy(",")

var declineReason = error.exception.cause.errorMessage.typedValue.value

I have tried

var declineReason = if(error == null) vars.errorDescription else (error.exception.cause.errorMessage.typedValue.value default "Bad request") as String

Also tried

var declineReason = if(error == null) vars.errorDescription else flatten(error.exception.cause.errorMessage.typedValue.value.message)

error.exception.cause.errorMessage.typedValue.value returns null.