problems with new uprated flywheel and clutch

hi i have just bought a new sachs dual mass fly wheel and helix clutch for my fabia vrs and have taken it to a trusted local mechanic and he says that he thinks one of the parts arent correct as it doesnt seem to fit together correctly so i rang awesome GTI where i got the parts and they say the part numbers on my invoice are the correct one for the parts for my car. was wondering if anyone could help with any ideas