If you do something for a friend and they say they will pay you for it, don’t expect it.
I have had many friends and relatives in my life ask me to do something that normally I would be paid for by others. I told them when they asked I didn’t mind giving my time to them, but they insisted on paying me. Ok then.

Why am I sharing this? I remember Judge Judy’s episodes where friends/relatives sued each other to recover small amounts of money. The money amount was smaller than the cost of the plane flight to California to attend the court case. The shows pay for the flight/accommodation generally but that isn’t the point.
The point is that when you do something kind for others don’t expect people to keep their promises of payment or anything else. I don’t know why people don’t remember their promises. It doesn’t matter. Just know up front up when you decide that if you give someone money/help you generally will never get any benefit from doing so from them.
This is reality. In another episode of Judy Judy had a friend who leased a car for her friend because she couldn’t qualify for one herself. The friend was not responsible for it and went over the mileage amount which cost her friend a lot of money. She was suing to recover damages and Judy Judy denied her and called her an idiot. It is wonderful to want to help others, but there is a line between helping and hurting someone. She hurt herself and her friend by not allowing her to face the consequences of her decision not being able to qualify for a car.
I don’t care about the money. This isn’t anger or sadness towards those people. I forgave them a long time ago. This is just to point out that when we help others, we shouldn’t expect to get paid even when we are promised we would be.