Spring binding can sometimes cause this issue, however you may want to contact Strike Industries, they may have more information available.
I have a gen 5 glock 23 and have 3 of these for it. You are gonna want a magazine loader for the break in period.
You gotta put the mag holder on and keep pressure on it with your thumb and slam the base of the mag into your other hand, it'll go down and you can add another round, and so on.
It's an extra strength spring, so you gotta break it in.
Unload and reload it a few times to make sure the spring is working properly.
I have not had any issues with mine.
Try unloading and loading it a few times. I did this on my G19 ETS mag and it worked.
NO, a big NO to the "experts" wrong answer.
The correct part number is SI-EMP-G9&40
Here is the link;
https://www.opticsplanet.com/strike-industries-extended-magazine-plate-for-glock-17-glock-22.html?_iv_code=3Q-PME-STRIN3-SI-EMP-G9&40
The EMP G19 will not work on a G23.