My Rumpus Alias changed, but I didn't do it!
The Rumpus Alias system was deployed on September 21, 2018. If you had a Rumpus account before that time, your Alias was changed along with everyone else's (you can change it again whenever you please).
If your Alias has changed since that time you might have a security issue. You should remotely log out of Rumpus and make sure that no one has access to the 3rd party accounts (email, Google) that you use to log into Rumpus.