A surety is discharged if the creditor without consent unconditionally releases the principal debtor...........

A surety is discharged if the creditor, without consent, unconditionally releases the principal-debtor; the reason for this principle being that:

The release extinguishes the principal obligation

Such release adversely affects the right of the surety to sue the principal-debtor and deprives the surety of his right to compel the debtor to perform his own obligation to the creditor