Once complete, the user will need to reset the password for the Apple ID. When the Apple ID is locked, the iOS settings app will pop up a window prompting the Apple ID settings to be updated. Once locked, we will not be able to access services such as iMessage, iCloud, and Apple Music.
Some netizens speculated that there may be groups trying to hack the Apple ID on a large scale, which led to this wave of Apple ID being locked. Of course, there may be a bug in the Apple service. Is your Apple ID locked?