You're trapping the trigger, which as you said, is not fully releasing it to allow it to reset.

You'll have to make a deliberate effort to release it for a while until you can get in the habit of doing it every time.

It may also help to hold the shotgun a little more firmly in case you think you are releasing the trigger but actually there is just slop in your gun mount.

You’ll get over it with just a little practice.

All the best,

Kyler

I had a problem with my Beretta O/U with failure to fire second round. The trigger was too long and would hang up on the trigger guard so it wouldn't reset !!Had to cut it shorter. Otherwise it's discipline to deliberetely release the trigger.