After a recent bug made daily missions unplayable, Ubisoft appeared to have patched the bug causing the problem. Unfortunately, they also appear to have wiped HUNDREDS of Xbox One players accounts on the game in the process. The first instance came from a Reddit thread by Ramm94, who was clearly upset...

I've seen several reports of players' character getting wiped out, including myself, after the patch. My first login was fine, and I logged in briefly to check the update and everything seemed normal. The next login attempt, I received a delta or mike error while attempting to login, so i reset the game, and then my character is gone. I hard reset the X1 to clear the cache, but to no avail. I had 150 hours into that character. This is totally unacceptable.

An admin for the game jumped into the thread asking for gamer tags of anyone else who was experiencing the issue. He was met by at this time a couple hundred other players who all had the same issue. As of this morning we have no update from Ubisoft as to when a fix will happen, but we will keep you updated as soon as we know. Until then, players who haven't lost their accounts yet are advised not to log in to avoid doing so.