This issue happening because tracking settings on the device. You have to switch on tracking Critical Strike app. Thus you can fix the issue easily.

How can I fix "Invalid Facebook token" issue?

Please follow the steps we explain now;

1) Tap to iOS settings icon,

2) Tap to General
 

3) Tap to Privacy & Security

4) Tap to Tracking

5) Switch on Critical Strike app then your issue will be fixed.