Index Match Issue Not Working in all the cells

Hi,
I'm trying to lookup values from components sheet into Sub Assemblies sheet with specific criteria, my formula is working in few cells but not for all.
Also, advice if the formula that i have used is correct or not.
Can someone help me on this please.

Change the bits in red:
=INDEX(Components!$C$3:$P$42,MATCH(C3,Components!$A$3:$A$42,0),MATCH(B3,Components!$C$2:$P$2,0))

B.

Thanks B M H O M D !!!

Thanks a Lot Paul !!!