Failing to enable fly on region enter

[sebastiantho]

My spawn is in a different world and so people have their flight turned off whenever entered. To fix this I've tried enabling it through command-on-entry to make sure only those with perms will have their flight enabled. This however isn't working, the command is being executed, as I can see the essentials plugin saying it is enabled, however it is never in fact enabled.

Is there any way to fix this, or any other way to automatically enable fly on entering the spawn world, given you have the permissions.