Noobie help Squad Battles

[Balratmort]

Hello,

I guess this will be a stupid question for all you grognards here, but I'm stuck in the tutorial game of my first squad battle game.

I need to call support to shoot a barrage of chemicals, but when I select the hex from which the mortars should shoot, I get an error "No valid leader or vehicle has been selected to call support". 

I tried almost everything but nothing can make me give support orders.

Any clue?

Thanks,

Rudi