Guild Wars 2

This is a Norn story quest.

I’m stuck because the mortars will not fire far enough.
Anyone else do this story?
Can you help?

I sent in a ticket thinking this is some kind of bug, but I have not received an answer.
Am I doing something wrong?
I can move the mortar cannon left to right and vice versa, but have no control of distance that the mortars are shot.

I got my answer.
I needed to hold down the mortar shot instead of just quick bursts.
Needed to let it charge up so that it would go the distance needed.