Bug in Package Project that does not occur in the Editor

I am having a bug with my levelling system that happens in the Packaged Project but not in the Editor.

This is a Blueprint UE 5.2 project, and as such it is hard for me to figure out what is happening in the Packaged Project. its a 100% repro bug.

In case that would help, here’s the bug in question:

After dying-restarting a map (eg. after saving and loading a player data save file), my “level max XP variable” is not set correctly and sends my leveling system into a level up loop without end.

Any idea how this behavior mismatch could happen?

Thanks in advance!