GSG STG 44 Jammed

[blista77]

Out shooting at range an around 200 rounds the gun the gun jammed half way open an was completely stuck, was able to get the gun apart at home.
It looks like pin got lose an is catching , I'm wondering do I whack it back in, or try to source a new 1, an is this common.

Any tips is appreciated

https://ibb.co/2jVJMdH

Put about 2000 rounds through the rifle, this is my first issue ever, looks to be simple issue

 

[OkayShooter]

Pictures would help.

 

[OkayShooter]

I never had that happen with mine, when I had it. And haven't heard my buddy that owns it now, complain. I would look at a new pin. If it walked out once, it will walk out again.