You issued a receipt, didn't you? If only your name can't prove it, is the name of your company on the receipt? Some units print their own receipts, reimbursement forms, etc. Take a look. If there is, so much the better. If not, you'd better find the other party to sign. If you can't find the other party, write clearly the reason for receipt and the name of the other party's unit (or individual). Anyway, the more detailed, the better. This is the original voucher. If there is no remedy, report to your superior accountant! Remember to write a receipt clearly in the future. The receipt issued by our unit needs to be stamped with a special financial seal.