Need Help ( Complicated IF function - Maybe- )

Dears,
Below is a scenario to what I need.
I had borrowed 50$ from Mike and then 60$ from Ahmad, 70$ from John. Now I've 100$ and want to return their money back respectively starting from Mike and then Ahmad and if anything remained to John. ( The amount I've is usually changing i.e. now 100$ a week later 50$, so when I bring changes in total amount I have, changes should appear in amounts I gave to the above mentioned people).
I'd already returned back 10$ of Mike few days ago. attached sheet may help you better understand me and help me back. Thanks
I need this for a large amount of data.

Your kind support in regards is much appreciated.
Help1.jpg
Help.xlsx