What is the legal ruling regarding a flat seller who violated the terms of the contract and filed a malicious lawsuit accusing the buyer of breach of trust, despite the buyer's commitment to paying the installments?

The builder has committed grave errors against you, and he is a sinner in the sight of Allah, for Allah Almighty says: "And do not consume your property among yourselves in falsehood," and because the Prophet, peace and blessings be upon him, said: "Indeed, your blood, your properties, and your honor are sacred to you." We advise you to be patient. As for revenge, some scholars have permitted it only in financial matters, meaning that the wronged person has the right to reclaim his money by any available means, provided that there is no fear of discord or attributing a vice to him.