It would probably help to know what the cream is.
My vet had me try a 60% salicylic acid cream on Olivia's corn probably 7-8 months ago. Cover it with duck tape, then put a sock on her foot, leave it on overnight, remove it in the morning.
He had removed the corn, then it came back, it fell out on its own, then it came back again. At that point he suggested we try the salicylic acid experiment (he'd successfully removed a human wart with it in that strength and thought it might be worth trying on a dog corn.) It worked great. It softened up the skin around the corn and made it more comfortable for her to walk the next day. At her next appt. (2 weeks) he scraped off the dried up skin and the corn came with it. Hasn't come back yet - on that toe. Now, a new one has started growing on her opposite foot but ironically on the same spot on the corresponding toe. Go figure! Just finished putting on the first application of the cream 15 minutes ago. I'm curious to see if it works just as well again.