It rather sounds as if there may be some bits of paper left behind in
the printer.
You don't say what make the printer is. Many of them have a paper feed
button.
If your printer does, try pressing it with paper loaded as if for
printing. Does the
paper feed through? If not, the likelihood is that paper is still
jamming the roller
and you need to try to remove it. Incidentally, do not fiddle inside the
printer
internals with the power connected!
Let us know the make and model of the printer and someone may be able to
offer further advice.

I thought it was probably a bit of paper left in there but unlike the
inkjet i had, with a laser there doesn't seem to be any bits around
the drum to lower or such like a photocopier has.No paper feed button.
It is a Samsung ML2010R which was supposed to be in the email header.

I broke one of these printers trying to take it apart. It is small and
everything is very tightly packed together. Be careful. If you take it apart,
chances of putting it back together in working order are slim. I am not good at
working with tiny bits, so it could be just me. Try blowing it out with
compressed air after releasing the catches, if it is a tiny bit. If it is a
larger bit do not use anything sharp to try to pull it out as you will scratch
it and make it worthless.

It seemed this printer got 'stuck' somehow. I tested it on windows and
it was fine!

Somehow CUPS seemed to have a glitch. Accessories~>Manage print jobs
didn't permit me to delete the queue. I went to
http://localhost:631/printers as well. Then shame on me - took the
easy route out deleted the printers and installed again. All works
perfectly. So there wasn't a piece of paper jammed in there after all.