Fenland Breakers fenland breakers car part automotive wrong misled March, Nationwide

I purchased a catalytic converter for my car (a Suzuki Liana) from Fenland Breakers, Commercial Road, March, Cambridgeshire PE15 8QP in March 2010. However, although the make and year of the car were correct (I assume) the part did not fit. When I made further enquiries with an Ian Johnson from Fenland, he said that he would send a connecting part the next day that would solve the problem, alas the part never arrived. After waiting some time and a number of email and telephone conversations (getting nowhere) I decided to purchase an alternative part elsewhere.
On the 19th April I emailed Fenland saying that I would like to return their part and receive a refund. In a phone call I was given instructions on how to return the part and it was intimated that my postage costs would also be covered since I was asked to also include a copy of the postage receipt.
I returned the part on the 27th April, through the Post Office. The barcode tracking number was FWKM2101355GB. I placed the receipt (for £12.99) in the package. However, I also asked for a copy of the receipt and I may be able to trace this if it helps.
On later inspecting my credit card statements, I noticed that there had been no refund to my account. I emailed on the 28th July to enquire and then again on the 2nd August. However, there did not seem to be any serious attempt to make a refund; I was told that "Gail  was not in the office at the moment". Note also the fact that the part was returned was not questioned.

I am still awaiting a refund today, almost 1 year since I purchased the part.