My Necchi sews slowly

Question

I had my Necchi cleaned and tuned up because it seemed to be sewing

slower than usual.  When I got it back, it seemed ok but wasn't any faster.
I think it is the foot switch.  I mentioned that to the service man
and he just looked at me blankly.  He said I had to keep it oiled.
I do not use it very much.  But sewing so slowly, I don't use it at all.
It jams.  Not enough power to get stuff through the pressure foot.

I brought home another machine for $300 but it was a piece of junk.
Very light weight.  Very noisy.  Nothing like my Necchi.