Bitcoin Wallet Password Selection

I have a bitcoin wallet, I have been working with bootforce for 4 months now. So far without result. The interesting thing is that when I enter a password that is not valid, it says: The password is not valid. But how do I enter the password that is needed: it says that not all keys are decrypted. As soon as I try to change the password to another in the Bitcoin core program, the program is reloaded without changing the password. Maybe someone faced such a problem?