Did you switch to a different platform?
Gems purchased from a specific platform cannot be transferred to a different platform due to store regulations.
For example, if you switch from Android to iOS - you will not be able to access the Gems you purchased on Android from iOS, and vice versa.
You can return to your previous platform to access the remaining Gems that you left on that platform.
If you intend to move from one device, we recommend that you use up all your Gems before migrating.