Help mortage advice

Jennyz123123_2

Hi. I'm not sure if I'm posting in right place but here goes anyway. Me and my ex bought a house together 10 years ago. He put down £4000 deposit. Five years ago we spilt and I moved out. I tried to remove my name from the mortage but he could not keep it a his income was low so for his stayed I stayed on mortage. Two years ago he moved out f the house without telling anyone. The first I knew was an eviction hearing from mortage company as mortage had not been paid. I was renting at the te with my new partner amdnour son. So I decided to move back into the house that I used to own with my ex. ( he was now living with new partner). My new partner emptied his saving account and paid of £5000 mortage arrears and a £8000 loan which was secured against the house from my ex. We have lived there since, paying the mortage and getting myself debt free. Today in the post I received a letter saying they are putting a bill on the house for £5000 my ex has in debts. Which will have to be paid whdn the house Is sold. I have asked him to take his name off mortage several times over the last two years but he is refusing. Is there anything I can do to force him to remove his name. In total me and my new partner have paid £13000 of debt he left but he is still saying he wants more!!! The house is in negative equity. He is settled with new partner and kids buthe is so stubborn.