The Last Known Evidence of a Roman Legion

The last recorded sighting of them is in a d one o seven they are at that point. The question is, were they destroyed? Did they mutiny? In which case, where they would have been punished and disbanded? Were they transferred to another part of the empire? We just don't know what happened to them. But at some point, five and a half thousand men disappear from the official records. So i wonder we could dig into some of these theories a bit more.