The application you have selected does not exist iPhone [ Solved ]

Apple's system status page was not initially displaying an error when the problems started, If you getting an error ‘Application you selected does not exist’ when you try to log into my iCloud account or App Store. The moment I tried I got the error "The application you have selected does not exist".Since then Youcan't log in to any iCloud Apple ID related thing at all... (App Store, iMessage, etc...)

The support site says that some users may be unable to sign in to their ‌iCloud‌ accounts and may also be unable to access ‌iCloud‌ web apps and ‌iCloud‌ Mail. Some users are seeing a message about needing to verify their ‌iCloud‌ accounts, and when attempting to sign in, are getting an error message that says "The application you have selected does not exist." Other iCloud-based services such as Apple Pay are also not working properly, and app specific passwords are failing.

As of 8:30PM ET, Apple’s system status page says the issues affecting iCloud have been resolved. But the company’s support account on Twitter is still replying to users experiencing issues and saying the company is actively investigating.

Update: According to Apple's System Status page, the ‌iCloud‌ issue has been fixed.