Clean it with denatured alcohol or lacquer thinner; it's gunked up with dust and old adhesive. Don't let the lacquer thinner sit on it too long, it can dissolve some plastics/vinyls.
Let it dry for a good while before attempting to stick on the abrasive, because the solvent needs to evaporate back out of the plastic.
Casey

Thank you, Casey!
I thought it might be trashed. '
I really like this tool.
C.

"Clean it with denatured alcohol or lacquer thinner"

Or even some warm water and soap.

Lacquer thinner will eat the sponge padding behind the cover of the pad.

Replacement pads should be a parts item. I've bought several (Bosch) brand over the counter at a local dealer. You may even be able to replace them with hook & loop, if you are so inclined.

"You may even be able to replace them with hook & loop"

Hook & loop is painfully expensive unless there is a lot of use to pay back for the extra cost.

It allows the paper to be removed and then used again at a later date, vs PSA discs that are pretty much wrecked during removal.

It's not the pads that are the issue.
It's the flat round part where the pads stick.
Or don't stick at the moment.

I'm going to try to clean it up.
I'll let you know what happens! :)

The "flat round part" is usually a thin layer of plastic applied to the sponge pad to keep dust out of the sponge and provide a better surface for the PSA pads to adhere.

'Hot' solvents can damage the foam portion behind the thin layer.