Hey, Luis. The magnets should be good, the likeliest scenario is that the suction pads on the bottom of TWA are dirty and don't provide as much grip as they did.
If they're still in good shape and don't have curled edges, you can go ahead and use a damp cloth to wipe them down in one direction. This will help to bring back the grip.
Otherwise, we do offer extras here: https://store.tonewoodamp.com/collections/products-accessories/products/replacement-suction-pads-set-of-4
You're very welcome.
Hey, Luis. I'm so sorry that you're still having some trouble. Please shoot me an email at firstname.lastname@example.org with some photos of the replacements and I'd be happy to assist.