In AWS WebSocket Gateway Lambda how to return errors?

I am using AWS Websocket API Gateway. I have the following code in lambda and I want to return error to connected users

// Joi Validation
  const { error, value } = bodySchema.validate(body);
  
  if (error) {
    return callback({ statusCode: 400, body: "Invalid request" });
  }

But the connected user gets:

{"message": "Internal server error", "connectionId":"YT8ZZe4sBcwCGvA=", "requestId":"YT8cqFb3BcwFgVA="}

What do I do. I want errors to be sent properly. With statusCode and body.