What can i do to prevent my build to be different that my in engine game

My game dont behave the same way in engine and when in shiping build.
Example : item will not spawn or save won’t load in shiping but work perfectly in Engine.
I dont know what to do.
The save system is realy simple.
its a struct with a guid as i identifier and a bool that is true when the item has been used.
so when i load i check for the GUID and then check the bool linked to it.