I've got a few dead keys on this keyboard - any way to fix?

I've got a few dead keys on this keyboard - any way to fix?

Hi, I’ve got one of these keyboard - I’m a fan of it in general. It’s pretty high mileage, and they don’t make em anymore. Nothing is obviously physically damaged; my “U” key and a handful of keys on the number pad are just dead. Anyone have any thoughts on fix? is there such a thing as a diagnostic app for Apple keyboards? Thanks!