My transport helo's are flying off without orders or requests, though I can somewhat direct them, they also seem to be incapable of landing to drop off or pickup units.
Has anybody else had this issue?

Set modules:
Combat support > Combat Support Transport(With desired helo in field). This is correct, no?

Mine do this too. Yes with vcom. It happens when the base comes under attack.
You need a bigger safe zone around your base to solve it as once they fly off they are rendered combat in effective until destroyed and respawn.
They will also only land if there is a shit tonne of room for them and they will land on top of trees so make sure it's a field lol.