Shocking service regarding warranty claims

I bought a 1 year old Haval H2 from Thorp Motors in 2019. Only later did we realise that 3 rims were silver and 1 was bronze. We have been trying to get this resolved since mid-last year with nothing but excuses and no replies from Thorp, despite taking the car into Torp for them to take photos and submit for a warranty claim. 8 Months later we have brought this again as the rim has now started to deteriorate and is cracked and pitted. Thorp eventually sent someone out to take more photos, he admitted that rims do not actually come in this colour??? However the claim has now been rejected. This is completely unacceptable service from Thorp as well as Haval.