I can't see some of my friends in "Current Level" Leader Board after I changed my mobile device (Android). Previously I was ranked at #8, and currently i am ranking #3 when using my new phone. 5 friends were missing in the Leader Board. I tried to uninstall the apps and reinstall again, it's still the same.
Note: The friends are still here at "Rank" and "Level this week". Only "Current level" is not updated.