The wallet profile was missing on the PC, as well as the passphrase to restore it. I don't think it's my PC. I believe that the actions were carried out on a third-party resource. Does Electrum have tech support to check this? How can I communicate them?
Probably you install software that has a malware or you get from downloading files. The disappearance of the wallet.dat is a clear sign that your computer is compromised. Im curious how your passphrase is missing while you should put this on safe place?
Theres no electrum support and confirmed transaction is irreversible. Even Satoshi cant recover this.