Using coupons from Google play

I have been playing candy crush soda for years. Last year I exchanged points for coupons on Google play. When I try to exchange the coupons this game isn't on my list of games. Don't know why because I have exchanged coupons for this game before no problems. I have tried everything on the Google play help section, contacted Google help desk and followed their instructions but nothing. How do I get this game on my list of games in Google play so I can use the coupons? can anyone please help?