You can't get killed unless you got tpkilled/you was in a pvp enabled area... And we need more infomation you can't just say "someone killed me". And the title doesn't make sense with what you're saying. And wrong section too..
Btw what pvp is it?? pvpmine or the real pvp because if it is the /warp pvpmine u can really fly there on top of the mountains but i dont think that pvp is enabled on top of that secondly if it was on /warp pvp flying is automatically disabled and if u get killed in pvp its your fault even though the player is invisible. Btw also i have tried that in /warp pvpmine the mountain side on top of it i tried to fly there and and fly down the pvp enabled area my fly was automatically disabled. But if you are tpkilled you would have remembered the person who tpkilled you and have sc about the player and make a ticket because as i see your situation you are the one who must be responsible for it and if you dont have any evidence then there is now way for you to get justice on the action that has been done to you..... Anyways becareful next time...
Im pretty sure pvpmine and pvp arena will definitely remove player /fly.But then if it is a bugged,you could contact the staff though. Hope this Help.