"If you can't connect to the App Store, iTunes Store, or other Apple services" click here --> If you can't connect to the App Store, iTunes Store, or other Apple services - Apple Support
- If none of the suggestions work, try contacting Apple (see below).
If you see a message saying to try again later or there is an unknown error, see if it's a system issue: Apple - Support - System Status
Verification Failed "problem connecting to the server" March 2018 - Verification failed - Apple Community - Needed to connect over wi-fi and not through cellular.
And the opposite:
"Verification Failed, An unknown error occurred" March 2018 - update apple ID settings notification in … - Apple Community - "tried again with Wifi off and it worked"
Sometimes using a VPN use can cause problems. If you are using one, uninstall it completely, don’t just turn it off.
If those don't resolve the problem, I suggest you contact Apple:
Contact Apple. Click here --> Choose your country or region - Official Apple Support Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.
or:
Contact Apple for support and service --> "See a list of Apple phone numbers around the world."
Click here --> Contact Apple Support - Apple Support