Mortgage payment issues

[bigpete]

I separated from my girlfriend in 2017/18.sadly leaving my 2 children After negotiations via solicitors where I wanted to sell the family home, I eventually decided not to sell and agreed with my ex that I would pay the child maintenance as payment to the monthly mortgage cost with my ex making up any shortfall to cover the cost of the full mortgage.

Now after 5 year and many missed payments I am owed £4500 and have another 2.5 year until my youngest reaches 18 and the property can be sold as outlined in the separation agreement. This means that i will have to cover the cost of further missed payments amounting to £4000 and totalling £8500

I really want to sell the property so not to be further out of pocket.
Communication is only via solicitors with my ex, and I'm stuck as to how get my ex to agree that she owes me money and weather I will get the monet back later.

My separation agreed doesn't really cover this situation and I'm looking for further advise

Who is actually living in the house?
How is the other exP housed and how is that paid for?
What percentage of time do DC spend with each parent?
If the house was sold, how would the current occupants be housed?

Not enough info in the OP to work out if you are seriously considering making your own DC homeless just at the cusp of the GCSE/Alevel phase of schooling which will have a huge effect on their future wellbeing. No decent parent would do that.

Do you actually have a separation agreement? A legally drawn up one?

Yes. By my solicitor m

if you were not married the relevant information is who owns the house and how is the house owned - eh tenants in common, joint tenants, sole ownership,

why did you need a separation agreement ?

that’s it

The mortgage is in both our names as is the prooperty

The separation agreement was drawn up to with a number of various different clauses. Unfortunately there is nothing in there to say what if one party doesn't pay.
There is a clause to say if the mortgage falls into arrears then it should be sold. But I have kept up the repayment so not to get black listed or have the house repossessed.