Bind flysky fs-i6 to extreme flyer drone 2.0

Hi can anyone help with a bind issue I have? just got the flysky fs-i6 radio and when trying to bind to my extreme flyer 2.0 drone it not fully bind. Power up the drone and the bind led flashes fast, turn radio on in bind mode and the drone led flashes slow but not go to solid state. On the original drone transmitter I have to do a full on off sweep of the throttle then it binds but when I try this on the flysky nowt happens . Flysky tried in AFHDS and AFHDS 2. There is no bind button or connector on the drone pcb so I am a bit stuck. Hope you can help