Conditions for changing the guarantor: During the validity of the loan contract, the lender shall not change the guarantor without permission. If there is any change, you should apply to the bank and get the bank's permission.

Article 386 of the Civil Code: If the debtor fails to perform the due debt or the parties agree to realize the security interest, the security interest holder shall enjoy the right of priority in compensation for the secured property according to law, except as otherwise provided by law. Article 391 Where a third party provides a suretyship and the creditor allows the debtor to transfer all or part of the debt without its written consent, the surety shall no longer bear the corresponding suretyship liability. Article 543 The parties may modify the contract through consultation.