iPhone 12 complains about the text Messages and No Notification

iPhone 12 users complaining about the Missing Text Message and not even receiving the Notification on their iPhone 12 phone.

It's not been rectified that the users are facing this problem only on their iPhone 12 phones or the other IOS users like IOS 14.1 users and IOS 14.2 users facing the same problem. So far iPhone 12 users complained about this problem of the missing messages.