restore purchases

A few years ago I bought two premium plants and re-downloaded the game. Everything was fine, but when I tried to restore my purchases, it kept asking me to buy them again to use them. I just want my plants back, not a bad experience. If there's no way to restore purchases, I'd feel a bit ripped off, but that's beside the point. My story is simple: I bought two plants, and after years, it still won't give them to me and keeps asking me to buy them again.