Hi,
1. then you have a problem of logic. If it takes too long, you also may have a problem of what you are activating, the logic you have in your fsm is unlikely the source of the time it takes to process but rather the gameobject you are activating have components that take time to setup
to verify this, don't activate or deactivate but just output logs in the console and debug first like that, making sure the log matches your expectations and the values in the tables. then move on and actually activate deactivate, you'll narrow down the source of your problem quicker this way.
2: make your object to not be destroy on scene load, and then it will always be there. You should also make it as a singleton, so that you don't end up with duplicates should you go back to the menu.
Bye,
Jean