On top of all Favours ( the name of lender ) himself agreed that he is now happy and everything is now solved, why seriously why this red trust ?
Because I do not trust you. That's why.
He borrowed 0.05 BTC
40 days have elapsed
He has paid 8 days worth of interest
Therefore total payable should be 32*0.05*3%
= 0.048 BTC
It's entirely irrelevant whether the lender is happy or not to me.