hi all, thanks for suggesting things to help,
i couldnt attach the file as it was a bought/pay for file and so couldnt really share as that would defeat the point of it.
it would seem that there was a tiny part of some kind of editing way above where the model actually finished that had been left, simply editing that out in prusa helped. (had to download a second slicer in order to make sure for my own sanity.)