Save System via Game Instance stopped working after API 28 (and later)

Greetings everyone, I have 2 games made with UE4, after Google decided to accept apps only with targeted API 30, I made updates for both of my games. I use a save system via Game Instance which worked perfectly before API 30 update. Right now, if I create an apk with API 24 or lower targeted they work as the same but Google Play does not accept them as updates. If I make the targeted API 28 or later, the save system stops working.

I was using UE 4.24 with Codeworks and tought maybe that was the problem, I switched to UE 4.25 with Android Studio and the problem still persists. I did not find any solutions online and would like to hear some help. Thank you all in advance.