I am unable to backup my iPhone as my Apple ID is locked

When I tried to backup my iPhone 14 on iCloud a message appears saying An Unknown Error Occurred. I have no problem backing up my iPad. I still have a lot of storage in iCloud and there’s no problem with my internet provider.

Also a message appears saying my Apple ID has been locked. But after I’ve unlocked/reset it I still can’t backup my iPhone to iCloud.

[Re-Titled by Moderator]