Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
Printers tend to signal a paper jam, when paper won't feed into them.
Try checking on your paper stack, in the paper source. In case there is a setting telling the printer to look in an unusual paper sourcing location, put at least one sheet of paper in *every* possible paper source location, including all trays, and the manual feed slot.
After that, your problem is almost certainly either with the cams or the paper pickup/feed rollers. On the assumption that it is the latter, try this:
If the problem might possibly be owing to aging roller surfaces (for paper is fed into faxes and printers with rubber or plastic cylindrical rollers, that propel the sheet into or through the machine)... then you might need to clean the rollers in the problem area where feeding is not happening.
Remove all paper from the machine, unplug it, and open it so as to have access to the rollers in the problem area where feeding is not being done properly.
Take a clean high-quality lint-free rag cloth, moisten it with rubbing alcohol, and rub the rollers firmly all over their paper-contacting surfaces, three times over.
(If the rollers are hard to reach, there is another way to clean them... let me know if that is the case, and I will detail how to do the cleaning.)
Allow 5+ minutes for drying-off, then reload the paper, close up the machine where you opened it up, and then try again.