I can't seem to figure out how to remove the operating/cocking handle on a beretta 1200 shotgun . Can anyone help?

This is actually a Benelli [Beretta owns part of Benelli] so they should be almost identical.From the Benelli manual -after removing the barrel,'hold the cocking lever with your right hand.Press the carrier button with the left index finger, allowing the bolt to move slowly forward until it stops. -pull out the cocking lever'. Cocking lever =operating handle.I've only taken apart a 1200 once but there was only a minor difference between that and the M1-90 so I had no problem.

Thanks Mete! I got it out ,the gun dsassembled,cleaned and back together.