Incoming FaceTime calls are being rejected on iPhone 16 Pro after iOS 18.4.1 update

I’ve update my phone to the latest software twice and I’m still having the same issue. All of my incoming FaceTime calls are being rejected. I’ve checked the settings and followed all of the steps provided on other forums. I’ve even left my current service provider and went to another one with the latest phone and still having the issue.

[Re-Titled by Moderator]