"java.lang.IllegalArgumentException: Don't know how to encode" when header contains Authorization Bearer token

[LayMui-Toh]

My code snippet:

 String userAccount = String.format("{\"id\": null, \"login\": \"%s\", \"firstName\": \"%s\", \"lastName\": \"%s\", \"email\": \"%s\", \"activated\": true, \"langKey\": \"en\", \"createdBy\": null, \"createdDate\": null, \"lastModifiedBy\": null, \"lastModifiedDate\": null, \"resetDate\": null, \"authorities\": [\"%s\"]}",
                        login, firstName, lastName, email, role);

        System.out.println("USER ACCOUNT:" + userAccount);
       
        james.attemptsTo(
                Post.to("/api/users")
                        .with(request -> request.header("Content-Type", "application/json;charset:UTF8" , "Authorization", "Bearer " + idToken)
                                .body(userAccount)));

I got this error 
java.lang.IllegalArgumentException: Don't know how to encode {"id": null, "login": "john", "firstName": "john", "lastName": "tan", "email": "[email protected]", "activated": true, "langKey": "en", "createdBy": null, "createdDate": null, "lastModifiedBy": null, "lastModifiedDate": null, "resetDate": null, "authorities": ["ROLE_ADMIN"]} as a byte stream.

Please use EncoderConfig (EncoderConfig#encodeContentTypeAs) to specify how to serialize data for this content-type.
For example: "given().config(RestAssured.config().encoderConfig(encoderConfig().encodeContentTypeAs("Bearer eyJhbGciOiJIUzUxMiJ9.eyJzdWIiOiJhZG1pbiIsImF1dGgiOiJST0xFX0FETUlOLFJPTEVfU1VQRVJfQURNSU4iLCJleHAiOjE1NzgxNDIyNDl9.QZ5jMLVOjrfawVTYrUV2IXigzZuzS38bBMGGRHe6IvZ7lK3w8WMsdtNF8qkpjAgov14TllATXuyxJ5fBCIWvCg", ContentType.TEXT))). .."
        at io.restassured.internal.http.EncoderRegistry.encodeStream(EncoderRegistry.java:132)