Trigger arrived with screw back out - True Precision Axiom Glock 43/43X/48 Pistol Trigger

I tried to install this trigger on my g43x and it wouldn’t fit it. After further inspection the screw that holds the trigger on was half way back out. I tried to reinstall it but none of my Allen keys would fit. I don’t understand why this screw isn’t permanently installed like the original Glock trigger. Even if it did fit, how many rounds would it take the vibrate out and cause a malfunction. For a $100+ trigger this is unacceptable. Don’t buy it.