2000 plymouth voyager transmission problem

the problem is now the transmission works only because the car has been shut off since saturday. but when it don't want to shift gears it won't go passed first gear. what could be the problem. could it be limp mode.

Limp mode won't let it shift past second gear and usually turns on the service engine soon (SES) light. You'll have reverse. Sure it won't shift to second gear? Check the fluid level and change the fluid and filter if it's been in there a while. If you see any debrie in the pan more than grit on the magnets head for a shop. Have you checked for codes?