In order to borrow money, I mortgaged my house to someone else and made a mortgage registration, but in the end that person stopped borrowing money? What should we do?

Go directly to the registration agency to cancel. Mortgage is a kind of property insurance. Mortgage is based on the principal creditor's rights, and your principal creditor's rights have been eliminated. How can there be mortgage debt? Just go and evacuate.

Mortgage registration is only administrative registration, and there is no statute of limitations. As long as the creditor's rights are eliminated (the money is paid back, offset or for various reasons), both parties can cancel.