Is the land permissible for us, and is it obligatory to pay money or a penalty clause to the uncle who forged its sale contract?

If it is established that the land owner signed the contract presented to her by her uncle without knowing its contents, then the sale is invalid due to the seller's original lack of intent for it. Consequently, none of the rulings pertaining to a sale apply to it, and the land remains the property of its owner. If she took money from her uncle, she must return it to him. As for the penalty clause in the contract, it is not to be considered due to the contract's fundamental invalidity.