When a customer files a debit card transaction dispute, Reg E requires that we give them provisional credit within 10 business days from the date the dispute was filed. If the merchant can provide that the transaction was valid then the dispute we file with our data processor is represented. I need to know the time frame following the re-presentment and the procedure for debiting the customer's account.

I'm not sure I understand your scenario.

The merchant processed a debit request.
You paid it.
The customer disputed it.
You paid a provisional credit, giving the consumer your money on a temporary basis.
You decided the claim was valid and told the customer to keep the money.
You go to the merchant and ask for your money back.

The merchant's transaction has already been deemed unauthorized. They should never be able to run it again.

The merchant can provide documentation that the transaction was valid therefore there was no error on the customer's account.

Depending on the type of transaction, the bank has 45 or 90 days to conclude the investigation. If the re-presented debt comes in after this time period (when you have to make the provisional credit final), the bank will eat the loss. How long the merchant has to repreent thetiem will be based on your processing agreements that may not coincide with the Reg E timeframes.

If this is a chargeback you are referring to, under both MasterCard and Visa rules, the merchant must provide representment by the 45th day from the date of the chargeback. If this is a mail/internet type order, have the customer review the documents provided by the merchant and if they continue to contect the charge sign an updated letter advising they reviewed the documents and still claim it id fraudulent. You will need to do your 3rd chargeback (MasterCard) or Arbitration chargeback (Visa) within 30 days from the date or representment.

If you are beyond the 90 days for a POS dispute, the bank must honor.