iPhone keeps rejecting my passcode after WiFi router reset

About a week ago, my iPhone 12 mini just started rejecting my RIGHT passcode wrong. I know this sounds like I don't know what I'm talking about because that just can't happen, but trust me, it was my correct passcode. It won't accept my Face ID, only passcode, and the passcode was showing as incorrect.

This started happening after someone had switched off my wifi router, and switched it back on. Of course, I didn't think much of it then. Anyway, after several failed attempts, I had to restore my iPhone.

Guess what, I switched off/on my wifi router again today and right after that, the same thing started happening! iPhone won't unlock with the correct passcode!

I have no clue how my wifi can screw up my passcode, but that's the only pattern I have observed.

I am restoring my iPhone again as I am typing this, but this is no solution. Any help would be highly appreciated!