A lawyer's laziness in performing his agency duties causes damage to the client's rights and interests, and he can go to the Lawyers Association to complain to the lawyer.
However, the behavior of not replying to the message does not belong to the lawyer's laziness in performing his agency duties, and usually does not cause any damage to the client's rights and interests. Lawyers are very busy in their daily work. If this lawyer is in court or performing filing, investigation and evidence collection, there is no way to get back and forth news.
If you are not satisfied with the lawyer's working style and rhythm, you can ask for a change of lawyer or terminate the entrustment relationship. This is the right given to the client by the lawyer law, so you don't have to worry about any liability for breach of contract.