Pipehawk plc in Alton

Hi, a number of years ago I bought a gpr unit (12000pounds) from pipework plc, however on demo the unit stopped working and the demo had to be aborted, at this point I lost confidence in the product and cancelled the transaction and asked for my money back, the company would only give me a credit note for 9000 inclusive of vat which I still have and is valid and will never use, I'm angry that my money seems lost, I tried to get it back through a lawyer but no luck, by the way anyone able to suggest a way to get this money back would get 1000 pounds, email martinhaulage@yahoo.co.uk cheers.