It's common when playing Minecraft to be kicked from the game with the message “Flying is not enabled on this server”. If you use any mods, or just keep getting this issue when the server thinks you're flying but you're really not, you can use these simple steps to disable the server from kicking players when it thinks they're flying.
1. Open the Fille Manager
2. Navigate to /minecraft/
3. Right click server.properties
and click Edit
4. Find the setting that says allow-flight
5. Set this to True.
6. Save the file, and Restart the server.