According to the contract, the seller can claim that the intermediary company or the buyer bears the liability for breach of contract and pays the balance. If negotiation fails, the party will sue in court, claiming that the defaulter shall bear liability for breach of contract and, if losses are caused, claim compensation for losses.

Legal basis: "Contract Law of the People's Republic of China"

Article 107 If one party fails to perform its contractual obligations or performs its contractual obligations inconsistently with the agreement, it shall bear the continuing liability. Fulfill, take remedial measures or compensate for losses and other breach of contract obligations.