My brother has a Hajj and Umrah office, and there is a woman who previously went for Umrah with him. She gave my brother's phone number to people to transfer money to her. The person transferring the money contacted my brother, took his account number, and started transferring her amounts of money periodically. After a while, my brother discovered that this woman is suspicious and is engaging in illicit activities, and money is being transferred to her for this reason. Is my brother sinful because money is being transferred to his account number and he is delivering it to the woman?