It can take up to 24 hours between the purchase and the gems to update in the game as our system needs to receive the confirmation from Facebook.
If you still haven't received the gems after this amount of time, please follow the steps below and take a screenshot for us to investigate deeper:

1) Log into your Facebook account
2) In the top right hand corner, click on the arrow pointing downwards
3) Click on settings
4) On this page you will need to click on the section called “Payments” on the left hand side.
5) You can then find the purchase you are having issues with
6) Take a screen shot of this purchase THAT INCLUDES your name showing you are logged in.

Without this information, we cannot confirm that this payment comes from you directly and you will need to request a refund directly from Facebook themselves as they are in control of all payments.

You can contact Facebook to request for this by clicking the link provided below:

https://www.facebook.com/help/