Legal analysis: criminals serve their sentences, but they still enjoy normal civil rights according to law. Creditors can claim their debts through consultation and litigation. You can bring a lawsuit to the people's court where the plaintiff is located. You can also ask the joint and several responsible persons. If there are more than two creditors or debtors, each creditor with joint rights has the right to require the debtor to perform its obligations according to the provisions of the law or the agreement of the parties. Every debtor who is jointly and severally liable has the obligation to pay off all debts, and the person who has fulfilled the obligation has the right to ask other persons who are jointly and severally liable to pay his share.

Legal basis: Article 678 of the Civil Code of People's Republic of China (PRC), the borrower can apply to the lender for extension before the repayment period expires; If the lender agrees, it can be extended.