New Home 509. I have acquired the above machine second hand, but the reverse button seems to be

Question

I have acquired the above machine second hand, but the reverse button seems to be stuck and the feed dog only moves a fraction in reverse.
Any advice would be gratefully received. My e-mail is [e-mail].

The needle on my machine moves up and down and the feed dogs are moving, but it seems that they are moving in the oppopsite direction. The fabric doesn't advance and everything gets jammed.