Hello o bought an rc nitro buggy 1/8th scale tool for a bash without shell on got home now the shell no longer fits the holes don't line up I put the front on and the back holes are a few cm out what could cause this?

Pics would help, but id guess at you bent something or something has come loose (shock tower screws probably) What type of car is it?

Bent chassis. I would also check for broken chassis braces.

Sounds like its a shell from a different car?

If you're talking about it being out by a few "cm" I doubt the chassis is bent (you would expect a few "mm" if it was bent - a few cm would render the car useless)