Playio's Mysterious Thing (Message Bottle)

I still don't understand what that system is. I once received a message bottle with a very polite message saying, 'Please click the store page or the action button below, and it will be reflected in your achievements.' So I clicked it... I don't really get it. Are achievements the ones on the profile? Or are they eligible for gem refunds? (Creators Gem or My Game Ecosystem) This is the most confusing system I've encountered on Playio. I wish there were proper explanations or tutorials. Devs...