I had this problem after updating my IOS device iPhone 6 to 13.5.1 - I have not used this phone for about 4 months and I'm trying to get it working.
Internet is fine but my emails and Google service also stopped working.
I wanted to wipe the device but I can't since I have to turn of the 'Find My iPhone' option which I couldn't since I can't pass the Apple ID verification step.