Is the creditor entitled to claim the land agreed upon as a down payment after the seller's family refused to sell and returned the money?

The question can be interpreted in two ways:

1. If what occurred was a promise to sell, not an actual sale: The land remains his property, and the money is a debt owed to you by him. 2. If the sale was concluded with an option for the landowner to consult his family, for a known period not exceeding three days: This sale is valid if his family approves, according to the majority of scholars. However, if this option does not have a specified duration, the sale is void according to the Hanafis and Shafi'is.

In any case, this sale is not enforceable, and you are only entitled to the money owed to you by your acquaintance.