My iphone cannot signing in

You probably are having an Apple server problem. See If you can't connect to the App Store, iTunes Store, or other Apple services https://support.apple.com/en-us/HT201400. There have been quite a few Apple server connection problems lately. Among other things, in the above document, see Check Apple’s System Status page. You can check there to see if the needed server is available when you need to use one.

Also, below are the alert messages given in the document. But, receiving others is a possibility. Use the steps in the above document if you see one of these error messages or a somewhat similar message.

·      "Cannot connect to the iTunes Store. An unknown error has occurred."

·      "We could not complete your iTunes Store request. The iTunes Store is temporarily unavailable. Please try again later."

·      "Could not connect to the iTunes Store. Make sure your network connection is active and try again."

·      "We could not complete your iTunes Store request. The network connection could not be established. There was an error in the iTunes Store. Please try again later."

See if anything here helps.

https://www.imyfone.com/ios-data-erase/9-tips-to-fix-there-was-an-error-connecting-to-the-apple-id-server/

https://appuals.com/fix-verification-failed-there-was-an-error-connecting-to-apple-id-server/

https://errorcodespro.com/there-was-an-error-connecting-to-the-apple-id-server/

https://search.yahoo.com/search?ei=utf-8&fr=aaplw&p=Verification+Failed%22+There+was+an+error+connecting+to+the+Apple+ID+server

Some other things you can try. Do you have access to another WiFi network where you can try? That has worked for several people.

Try a restart.

Restart your iPhone, iPad, or iPod touch         

Try a forced restart.

Reset Device.      

If necessary

Hard reset.        

Do a backup and try a factory reset. Then restore from your backup.

Restore to Factory setting.      

Backup - Restore your device from an iCloud or iTunes backup.