Lost the ability to control vehicles with mouse

[deadnome 10]

Hi, I've not played Arma 3 with vehicles for a while as I mostly play on foot, so I don't know if this has been caused by a patch or something else, but I used to be able to fly a helicopter with the mouse as usual, but trying today and all the mouse does whilst flying is control the free look.

Tried double tapping alt, holding alt, configure setting etc but nothing seems to work.

I feel like this is probably quite the stupid moment from me but I can't seem to figure what has happened.

If anyone could point me in the right direction I would be very much appreciative.

Thanks and sorry if this is the wrong forum mods.