Problems with in-app purchases

How Do I Request a Refund? How Can I Find My Google Play Purchase Receipt? I didn't get an item I purchased! How Can I Find My Apple App Store Order ID? I'd like to avoid unwanted purchases. Rules on in-app purchases and cancellations Where can I check my purchase records? I can't buy anything. (Purchase Error) I accidentally used an item, can I get it back? I closed the game while making a purchase. Was my purchase cancelled? Are there other ways of purchasing Crystals apart from buying them in the game?