Carphone Warehouse

Dont take your phone to the carphone Warehouse (bodgehouse) to get firmware flashed , took my N73 to get my firmware upgraded after a few problems with it the Carphone warehouse reflashed it it never worked again when I took it back to them they said nothing we can do even though they destroyed it contact Nokia.
Contacted Nokia thay are the most unhelpfull company I have ever spoke too they are refusing to send me a new phone even though their so called repair centre destroyed it ,it worked befor now it does nothing and the phone is just over 4 weeks old , I have now gone back my D600 it works and has worked for 2 years and am taking legal action against Nokia UK.
How can they sell phones that they know have firmware issues and not tell anyone about it, apart from the service centres.