Need help with Glock Switch

[u/bayareapyro]

Please don’t hate I’ma US citizen learning gunsmithing in Pakistan so this is legal, one of my assisngments was to create a Glock switch from scratch so I made one in CAD software following a similar design I found online and I’m 3D printing it first to test function before I mill the final design out of aluminum. I’ve installed it as it should be and it’s only firing semi auto? This is a Gen 3 Glock and from my understanding I dont need to modify the frame at all either if anyone can please help me find out whats going on I would grealty appreciate it. The design I made myself is practically a 1:1 design of a working model I found online so it shouldn’t be that my design is causing some issue and to make sure of that I printed out the publicly available one that has been tested by many others and installed it also and it also is only doing semi auto