Apple's unknown sender SMS cannot be deleted.

Does the subject want to ask, "What should I do if the text message from an unknown Apple sender cannot be deleted?" ? This situation is rare. Generally, if you have an Apple computer, you won't have this problem. The problem usually lies in Android, because some rogue software may indeed have some messages that cannot be deleted. In this case, you can use some 360, or others to forcibly delete or restart. You may be able to delete it after restarting.