False VA Overpayment

I received a notification that my VA Benefits will be reduced to pay off a $1700 overpayment from the VA.

1. I was not overpaid, how do I go about this because I count on that to pay my rent?

2. I submitted an appeal on July 1st and received a notification on the 3rd stating "your overpayment has been implemented on July 6th. We will be reducing your benefits to pay off your debt".

3. You added the issue 3 days ahead of when you sent me the email?

4. I reached out to my VSO to see if anything can be done but with the holiday I don't expect a response too soon.

Any advice on how to go about this? Has anyone else experienced this? What did you have to do?