Disputes over unjust enrichment do not belong to contract disputes. A contract dispute refers to a dispute between the parties to a contract because the contract cannot be performed or is not performed according to the contract. Unjust enrichment means that the parties concerned have obtained illegitimate interests without legal basis, and those who have suffered losses have the right to request the return of unjust enrichment. If the lost property is found, it belongs to unjust enrichment, and the owner of the lost property has the right to request the return of the lost property. Unjust enrichment does not exist as a prerequisite for a contract, so it does not belong to a contract dispute. Because others have no legal basis to obtain improper benefits, those who have suffered losses have the right to demand that they return the improper benefits.
legal ground
Article 122 of the Civil Code of People's Republic of China (PRC) * * * Because others have no legal basis, the person who has suffered losses has the right to ask them to return improper benefits.