If this happened, there's some serious corporate communications problems at UA.

If you decide to write an apology letter, include the opening of the account. You can say it was recommended to you by a CS agent (I suspect actually UA will want to know that), but apologize for it anyway.

Why did you want a new account. Are you tied to flying United e.g hub, schedule, work etc?

How many miles were lost, and how much were total earnings of the [illegally] sold GPUs?

Inquiring minds NEED to know? ;)

Yes. attempting to open another account w/o coming to agreement w/ UA on original issue just says to UA - "I don't care what you think, I'm going to do whatever I want to". Unfortunately, UA has unilateral discretion on this and OP's proven him/herself as unreliable when it comes to rules. OP can fly UA if it suits, but if OP wants to participate in another FFP he/she's probably going to have to go with another carrier (and abide by the rules). Pretty much kills all Star Alliance carriers one might have been hoping to credit to UA Mileage Plus, too.

This reminds me of an acquaintance I heard tell a story that happened to him about 3 or 4 years ago who was going through a divorce. He and his to be X were both mileage and status whores. Ironically it was about the only thing we ever had in common to discuss at dinner parties, etc. However, his zipper got a little loose on a couple twenty or so road trips. Divorce and anger ensue. He was only 50k miles short of either lifetime 1K or GS, and the X had all his mileage plus information as they both traveled for work quite a bit. She went on Craig's list and under his name sells all his miles and upgrades etc, intentionally breaking all UA's rules and being open about it. He got his letter within a couple of weeks. I had heard he had tried to get reinstated, but never followed up to see what happened. Still loved hearing that story, and it seemed of all our mutual acquaintances, I was the only one who got joy out of the story.

Schadenfrreude.

Oh I'm sure UA will sell him/her a ticket but you're probably right about his/her days with MileagePlus being over.

Yup. If I, say worked at United, I might consider making a post like this every now and then, just to keep potential upgrade sellers scared straight. I'd probably make at least a few other posts on different topics though, so forum members would think I was legit. Just sayin.

I don’t see why they can’t open a new account with a different address. Unless their name is very unique and easy to match.

DOB will also match.

You can check with Lucky perhaps. United shut him down and I am not sure if he is back on UA now.
At least it was not a chase shut down - cost me 4 years time.

That was very different, not selling miles or upgrades.

Tried to bring an overweight cat on board by swapping him in?
https://www.nytimes.com/2019/11/13/w...-aeroflot.html

If it's worth $0,.53 to mail a short letter apologizing and taking 100% responsibility with no excuses of any kind, go ahead and send it.

Don't expect anything and start figuring out what's next. I am willing to bet that opening the second account shuts off any hope. If all UA wanted to do was zero out your account and status, it could have done that.

I would not risk that. What if they find out a year or two downstream and shut that down too. What puzzles me though is why someone thrown out of a program would want to go back to that same program when options exist? I can understand trying to get reinstated so as not to lose accumulated miles, lifetime miles etc, but what would be the reason starting afresh to go back to Mileage Plus with a new empty account? Is it so much better than alternatives that we need to go lengths to disguise ourselves to open another account?