I forgot my passcode and kept entering wrong ones. In the end, I reset the phone and reinstalled the latest iOS (13.3.1).
Now on startup, it sends a 2FA code to a number I have never seen and it's not in the format of my country (Iran).
When I bought the phone (iPhone 6S), I put in my SIM card for the 2FA. I have received codes from Apple before on this same number. Now it's changed and I receive the error: "Your request could not be completed because of an error. Try again later."
This has been happening for hours so it's not due to low server capacity.