legal ground
Article 696 of the Civil Code If a creditor transfers all or part of his creditor's rights without notifying the guarantor, the transfer shall not be effective for the guarantor. The guarantor and the creditor have agreed to prohibit the assignment of the creditor's rights, and if the creditor assigns the creditor's rights without the written consent of the guarantor, the guarantor is no longer liable to the assignee. Article 697 of the Civil Code The creditor allows the debtor to transfer all or part of the debt without the written consent of the guarantor, and the guarantor will no longer be liable for the debt transferred without his consent, unless otherwise agreed between the creditor and the guarantor. Where a third party joins the debt, the surety's suretyship liability shall not be affected.