Sometimes purchases take a while to process and do not get delivered immediately. You may want to restart the game to enable a fresh connection to the server. There is no need to try purchasing the same item again - it should arrive soon!
If you still haven’t received a purchase made more than 24 hours ago, please contact iTunes support. All payments made toward the game are processed by Apple. You can reach them right here: https://support.apple.com/country-selector/itunes
If your purchase was made through Google, and you haven’t received your order after more than 24 hours, please contact us by submitting a request with a copy or a screenshot of your order receipt. The transaction ID (looks similar to this - GPA.1234-1234-1234-12345) at the bottom of the document must be visible on the screenshot.
When contacting us, please make sure you also provide your game account identifier; You can find it by first tapping Menu, then Options and finally About. It's the string starting with a #-sign in the top left corner of the screen.