I have a mode 5906 that the double acton is not working. It will work in single action or if i pull the hamer back. Does anyone know what the issue could be and how i can fix it?

This may be a stupid question but do you have the mag in when you are doing this? Most of the 5906's will not fire unless the mag is in it.

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Why duck?? It's a 9mm!

yes the mag is in. it happens when i am shooting the gun. the hammer will not stay back.