James Mathew Roofing company

I appointed David to re-felt my flat roof along with repointing my chimneys as water was damaging my internal walls to living room. David advised me once he started the works that he would have to melt the existing felt and day down a primer instead of new felt as he was struggling to lift the existing felt. He carried the work out in Feb 2019, and I have just discovered after trying to sell my property that he hasn’t even repointed my chimneys, even though I had stressed this is where the water was leaking in from. I even have it in writing he confirmed this work was done. I have also since found out after paying him just shy of £3000 that it would never have cost that much for the labour and primer at all. I have tried several times to reach out and speak to David to discuss, and I have never received any responses back!
I do not recommended this company to anyone!!!! Now I’m having to pay for additional works just to sell my home!!