Urban Company — Professional damaged my exhaust

For 21st May, i booked service from urban company for exhaust cleaning and chimney cleaning. While cleaning the exhaust the professional damaged and item and it stopped working. It was committed to me by urban company team that I can buy a new exhaust and share the invoice and they will refund me for the cost incurred.

Now, when i am trying to raise a complaint, no one is responding to the complaint and tmi am not sure what to do now. It's not a huge cost item but companies can't keep on taking advantage of consumers like that.