I know you're just being funny here, but it's a good opportunity for me to make comment that applies to several nuances of this situation: Although the OP had no part in causing this and in a lot of senses is the victim here, it still remains that a) the extra $100k+ is not their money, and b) they know it. AA and/or Amex can at any point wake up and demand the money back (well, within whatever statute of limitations applies to such a situation, which is probably at least 2 years). It's not really a fair situation, considering the OP has clean hands yet has to deal with it, but it is what it is. At least they'll have a good story to tell for the rest of their lives.

Going to Vegas would make for a better story :D and make you a champion sitting at the dinner table in Folsom.

I don’t think the money will become OP’s funds. Not sure how long AA has legally to recover them, but rest assured they will, eventually. And then the OP has to refund the money from their HYSA or where ever they stuck the money if they followed the advice by people here. And what happens to their lost MRs? Will the interest earned on the HYSA make up for that?

Remember that AA is the same company that goes after "lost" SWUs years later. You think they aren't going to go after 100,000 once they finally realize it's not the OPs? Which could cause an even bigger mess depending on timing than what could possibly happen now with his AMEX and his MR. As much as it's a hassle, the OP is right to clear it up now - for their own sake.

I'd definitely request a check and put the money in a HYSA. Based on today's rates you should be able to earn around $375/month on 100K. If there are any issues you have an obvious paper trail of what has happened as well as your efforts to rectify the situation. You can easily prove that you've done nothing underhanded and the money is available to instantly return to AA when they ask.

Reminds me of a time I got paid $90,000 more than I should have gotten for a company bonus (which was nowhere NEAR that amount). Of course I let them know and they were thankful for me to bring it to their attention once I wrote them a check to pay the money back. The reason I later found out was due to a code change they made in their payroll system (home grown, not off the shelf). Someone in IT that I knew, who had more detailed knowledge of the root cause, said they probably would never have noticed the error if I hadn't said anything. But I guess I"m not the kind of person who only does the right thing when people are watching. Usually... :D

At some point if you believe AA still monitors flyertalk, AAs left hand may have taken notice and it may be a while till the right hand is clued in.

Reminds me of a time when I started receiving mysterious extra line items on my paycheck. Long story short, in addition to my salary the system was sending me short term disability payments meant for another employee (who obviously didn’t get them). Resolving that via “customer service” (HR/payroll) didn’t work - unresponsive. Eventually after about five attempts and five incorrect paychecks I just directly emailed the global head of HR (I guess now called Chief People Officer) of the 50k employee company (with permission from my boss). That worked, but payroll could never completely work out how to unwind this as part of the money went into a stock purchase plan and my 401k. Not sure if the other guy/gal was ever made whole…

And what exactly would you do about the negative MR balance in the Amex account?

I'm not planning to "withdraw" the 6-figure credit from AMEX for a couple main reasons:

1. It could be misconstrued by AA/AMEX of an attempt to defraud them following their error, especially if this leaves a large negative balance of MR points that is reviewed by AMEX's RAT team. The misunderstanding and lack of common sense I've seen at both companies by giving canned responses and following algorithms to unique situations could lead to shutdowns at both AA and AMEX with no recourse. The only real benefit for me to withdrawing would be that my account balances are normal except for a specially-opened account to hold these funds.

2. As mentioned by other posters, the loss of 500K+ MR points should I have to repay AA by writing a check. While I would value $100K over 500K MR points as someone suggested above, they're not going to let me keep the $100K. The real value comparison is the loss of 500K points compared to interest from $100K in a HYSA for an unknown period of time before AA comes calling (from days to months, let's say ~$4000 if it takes a year to resolve). That comparison would not be worth the value of lost MR points.

I plan on using my AMEX normally by making purchases I can pay off at the end of the billing cycle if the credit is removed. I am not charging $100K+ of purchases that I can't otherwise afford because that credit could be removed at any time (as it should). I guess given the risks I see, the short answer is I'm not going to just let it go, and intend to keep escalating until a resolution. I also don't want AA or AMEX shutting down/freezing my account anytime soon as I'm flying on a big award ticket for an international trip next week.

Wondering if you might file a complaint with the CFPB (while it exists) just to get someone's attention at Amex if they aren't responsive initially.

I think this will get resolved in due time, either by Amex, AA or both. I'd give the process a few weeks to work itself out. However, I'm not sure how a merchant can reverse a refund. I deal with a credit card processing interface and don't see a way to do that in the UI or programmatically, but perhaps other interfaces have a way to void a refund. AA might request you send them a check or might be able to do a miscellaneous charge. Let us know how they eventually resolve this.

Are they still taking and more importantly processing consumer complaints?

https://www.doctorofcredit.com/cfpb-...-institutions/

Website looks like it’s been in the process of removal… :(

https://cimg0.ibsrv.net/gimg/www.fly...ba604e0a4.jpeg

in any case, while I understand that you just want to get someone at Amex at a level above frontline customer service tobe aware of the issue, it would seem odd to knowingly file a complaint against Amex for something they didn’t actually do.

I am sure someone at AA knows someone at Amex to help sort this out. Can’t be the first time that a refund needs to be reversed, and AA is likely one of the largest merchants for Amex.

Oh, well FFS. I'm sure this will evolve.

Well, OP has a -500k membership reward balance because of this transaction, and while I'm not opining on CFPB's oversight of the MR program, it doesn't seem unreasonable to want Amex to fix that.