A customer comes in and files a debit card dispute because they paid cash for their monthly phone payment, but then the merchant also debited their debit card. We give them provisional credit and ask for a copy of the receipt (NOT as a condition of the investigation and provisionally crediting). The customer keeps promising she will send it, but never does. We are coming up on the end of the 45 day investigation period. Can we take the credit back because she failed to produce the receipt?