Hi.
please look at any recycle bin you have available and search for the masterkey file. (local system, local hard drives, google drive, etc). Maybe you have deleted it by accident. Search your complete system for that file also. Maybe you have just moved it by accident.
If you are not able to restore the masterkey file (or one of its backups, named “masterkey.cryptomator.XXXXXXXX.bkup”), you can stop searching for a solution because you will never decrypt your files again.
FYI:
The “d” folder is your encrypted data.
The logfile: Where is the log file located?
The folder “Google Drive” is automatically created by google backup and sync, if googles backup and sync tool does not find the “Google Drive” folder where it is configured to be.
Therefore it was not a really a good idea just to move the “Google Drive” folder to a vault called “google_drive” without telling googles backup and sync tool that the folder that it has to sync is from now on the folder where your vault “google_drive” is located. Usually you place your vault into the “Google Drive” folder so it is automatically included into googles backup and sync.