Everything looks fine there. The issue might be in the parts between the slide and frame.
A picture like this, only focused better would also help.
Can you take the slide off, remove the mag and dry fire the gun? Check to see if the hammer is moving (silver part sticking out into the magwell, on the back of the grip). If that's moving, then check the valve knocker.
Make sure the mag is gassed up and then press on the knocker button. If it's working correctly, it'll vent gas out the top. Being hard to press is normal, but you should be able to do it with your hands, no tools needed.
If the knocker isn't venting, then it could be a sign of the mag being over gassed, which is causing the gun to not function, or the knocker is broken.
There's also a chance the mag catch is busted and causing the mag to not seat correctly. I couldn't really see a catch in the picture you posted, so that's another thing to check.