stalled marineland 200B filter?

I don't have this exact filter, but I'm pretty sure all Marineland Biowheel filters work the same. Remove the "U" shaped tube, there will probably be a plastic bracket that holds the tube in place...remove it too. at the bottom of that, there is an impeller suspended in a magnetic field. Pull the impeller straight up and out. Make sure there isn't anything down in the hole that's causing the impeller not to spin freely. Use a "pipe cleaner" type brush to clean it out if necessary. Reassemble.

take it into the bathroom

leave bio-wheels and media in bucket with filter water

then put under tap IN THE TUB.............and let the water run over the filter for like 2 minutes on full force......then take out......shake the filter....clean out the hole again.....clean impeller assembly and restart
that should work for sure......it did for me on my 2X 350 bio-wheels one got sand in it and stopped but its quiet now

If the impeller isn't turning, there is something keeping it from spinning.
That can be a single not very long strand of hair, a clump of algae, a grain of gravel, or a bit of plant stem.

Can you remove the U tube and give the impeller a little push? With my Aquaclears I have a 50 that after cleaning sometimes the impeller wont spin, I fill it up plug it in give it a little nudge and it goes, then put the U tube back in.

Yea, I also have to stick a knife or other slender and long object down to push the impeller to get it going. But I leave the U tube on, just turn it to the right and move it back as soon as it starts.
If it still doesn't work, can you return it? If not, contact the manufacture, wiring could be faulty.