What is the ruling when two witnesses testify that a man acknowledged owing an amount to someone, and one witness testifies that the debtor repaid it?

Primary text

If two witnesses testify that a man acknowledged owing a thousand to another, and one witness testifies to the repayment, the acknowledgment is established. If the debtor swears an oath alongside his witness regarding the repayment, the debt is discharged. Otherwise, the creditor swears that he was not repaid, and the thousand is established as owing to him.