Is it possible they weren't banned and it was a tor IP ban?
From the messages in /u/anonymous:
anonymous wrote to Tequila_Wolf on Jul 16, 2018, 4:19:55 AM
Hello. I am /u/somanythings. I learned that I have been banned. Okay. I don't know why but I don't want to argue. I have a request that I make and hope you will show some solidarity in accepting: please delete (or allow me to log in and delete) my post history and my username in all places it appears on the site the same like so many other users do when they leave.
Thank you for considering this request. I will log in here again tomorrow to check your reply. And I will not use this anonymous account for any posting. Only to finish loose ends.
Tequila_Wolf replied on Jul 16, 2018, 8:55:44 AM
I've temporarily unbanned you so that you can do the deletions you want. In a few days you will be rebanned. I don't know the circumstances of your banning and don't have the time to get involved but assuming you don't abuse this unbanning there should be no problems.
I recommend you use Tor to delete your posts, often it's possible to delete several at a time that way, instead of waiting for the page to reload for each one.
Good luck in your future endeavours.