Allow flying on a Nitrado server (with Minecraft modpacn)?

I've created a modpack and uploaded it to a Nitrado server, which includes a mod where you can fly with some armor (Fisk's Superheroes Mod, to be precise). However, the server does not allow you to fly in survival mode and you can't run it through server.properties.

I guess that there's no plugin available through the mods… If anyone knows this topic, then I would be very connected to it.

Hmm. Actually, you should be able to turn off the standard Minecraft Anti-Flight.