I can't be the only person this has happened to, and I'd love it if anyone who has also dealt with this can please let me know how you fixed it.
I separated from the military in January 2019 and received my final paycheck and the money I sold back for leave. I set up my final pay from the leave to be put directly into my TSP. I thought everything was fine, got money put into my TSP, got my final paycheck, and went on with my life. Fast forward to the end of last week; I get a notification of debt from DFAS saying I owe roughly $4500 due to an overpayment into my TSP. Oh, and if I don't pay by September 5th it goes to the creditors for collection and reports to my credit reports. Not a ton of time to work with here. I look at my TSP and see money went in a month after my ETS, but the same day about 2/3 of it is immediately withdrawn. I figured this was the money I wanted to be put in from my leave pay.
I call DFAS and they say that they are just the collectors and I need to contact the post I separated through. I called the post finance and they did some research and let me know that they didn't put a debt out. I call back DFAS and was told that I need to submit a DD139 (or 136, I don't remember which) to protest the debt and it has to be done through my last post. I call the post finance back (again) and they tell me that they don't submit those forms and recommend submitting a ticket protesting the debt. I also called TSP and they don't put out debts on people and had never seen this happen before. Basically, no one can even tell me what this debt is for, but I'm expected to pay it within 30 days or my credit suffers.
So, I've submitted the ticket and the expected turn around on an answer is 60 days. I'm worried that if I pay the debt I will be "admitting" I owe the debt and will have my protest go nowhere. I looked into a payment plan, but it looks like that has to go through levels of approval and it likely won't be approved before 5 September. Additionally, it turns out that the letter I received last week was their first attempt at contacting me about the situation, which I find baffling, since I've been out since January and also this is a large sum of money. I'm considering calling my Senator's military affairs aid to see if they can help at all. If anyone had dealt with a similar vague debt please let me know how or if you fixed it.