I mean after the ban on pagan religions imposed by Christians in the Roman Empire
You might be interested in an answer I wrote on Ancient Egyptian religion in late Antiquity.
https://old.reddit.com/r/AskHistorians/comments/diudkr/ancient_egypt_was_dominated_by_people_who/
The tl;dr is that the Ancient Egyptian religion died out in the 4th Century(ish) and was replaced by and large by Christianity though a few other prominent pagan religions were also operating at the time.