Claim

[Sapper 62]

Hi Recently posted on here regards a PPI claim,my ex made a claim for miss sold on a joint loan we had, short story he had a company and got half I called direct and got the other half ( he was trying to make claim without me knowing ) anyway he now wants me to pay this half to him as he paid the loan. Can I be forced to ? He pays the mortgage and no maintenance but now he has asked a solicitor I pay the mortgage out of that money for a year .originally he offered me a % of the claim to do the repairs on the house that he left., we are trying to sort a financial agreement where I leave his police pension alone and he leaves a future inheritance I am due as my mum passed a few months after he left, that I am ok with but I need to know if I can at least keep some of the money back to pay for repairs that he left.
Do I have to give it him back or can I keep some as a god will gesture as he has already spent his half of the claim.