First of all, you need to know what material your chin is filled with, whether it is injection, silicone or expansion prosthesis, and then you can know whether it is feasible and easy to take out the repair operation.
Second, go to the hospital for consultation first. If you can't get a satisfactory answer, you need to go through legal procedures.
Because if it is a regular hospital, the consent form will definitely be signed before the operation, so have you read the words on the consent form clearly? Not everything has to be solved by law. Do you want to complain or fix your chin?