Help needed for development in unreal engine. Can't get the game save slot to save on the quest.

I'm working on a game and got stuck in saving the levels. The same slot registers and saves on the pc, but does not save on the headset with the (apk) build inside the oculus headset.
I enabled the "use externalFilesDir" in the setting but still, the game is not saving.
Any help would be appreciated as I'm stuck right now and there is almost no info on google.
Does it have to do with storage permission because I see no option to give permission to "unknown sources" files in the settings?