Q: I sold a car to someone in installments. After he had paid some of the installments,
I told him that I was forgiving the rest of the money that he owed me
and I signed a waiver in front of a judge in the court. However, the next day I regretted having forgiven him the rest of the payments and he continued to pay the installments. Are these payments Halal (lawful) or Haram (prohibited)? Should I return the money that he has paid of these installments, (Part No. 13; Page No. 177) as I only want what is Halal? Please advise me and may Allah reward you with the best.
If the matter is as you mentioned, you have no right to take the money that you forgave from the indebted person.