(1) If the performance of an obligation of one of the parties to a bilateral contract becomes impossible by any cause for which the obligee is responsible, the obligor may demand counter-performance. The same applies to cases where performance becomes impossible by any cause for which neither of the parties is responsible in the case of mora creditoris.
(2) In the cases of the preceding paragraph if the obligor has received any benefit by being relieved of his or her own obligation, he or she shall return such benefit to the obligee.