A viewer on the 52 Cameras channel on Youtube has a Maxxum and the film counter stays at ‘0’. I ran through a few checks on mine that might be helpful.
First, the easy stuff — check that the batteries are fresh and making good contact. The LCD can be on when there’s not enough juice to run the film transport motor. LCDs are very low power compared to motors. Some people recommend against it, but I’ve had good results cleaning battery contacts with a pencil eraser. If the contacts are really corroded, take off the battery holder, take out the batteries, and soak the holder in white vinegar. When it stops bubbling, rinse it off, dry it thoroughly, and try again.
Open the back, turn the camera on, and push the back catch with something small like my trusty cocktail straw. Watch the sprocket — it should turn. With no film, my camera tries four times. You’ll need to push the button and slide the back release down so you can close the back again.
Last, there is a little roller on the inside of the camera back. It should turn freely so it will hold the film against the take-up spool.
That’s it for checking and verifying things I can think of. If anyone has more tips, please chime in in the Youtube comments. I was invaded by spambots and had to turn comments off on the blog.
The 52 Cameras Maxxum 7000 video link.
Worst case, check Etsy, shopgoodwill.com or that online auction site. Maxxums are still really cheap.