Noted first by 9to5mac, some users on the newly released iOS 13.5 update are reporting that apps like YouTube are not opening. When trying to open some apps users are prompted with a message saying “This app is no longer shared with you. To use it, you must. buy it from the App Store.” per the report:
Then, users can’t do anything except cancel the prompt or get redirected to the App Store. The issue is affecting random apps instead of a specific app, and although we don’t know exactly what this is about, this error message is related to iCloud Family Sharing.
Apple has not yet confirmed this bug or displays any issues on its status page. As the report says there is no current fix, although reinstalling the app may solve the issue. The error message relates to iCloud Familly Sharing and only impacts certain apps.
Some Apple Terminals users are reporting this issue on older iOS versions as well, with YouTube being a culprit.