MissingReferenceException when reloading level

I'm trying to implement a simple restart action for the current level in my game, thought this should be no problem but when I restart the level, I'm getting hundrets of missingreference exceptions and the game doesn't work anymore. It seems to be primarily in this line: return transform.position + (offset); The game sets the position of every actor at the start, so it is required that the transform can be accessed. I don't really understand why this doesn't work. Also, when I'm trying to access the gameObject for debugging purposes like print((gameObject == null)); Unity just freezes and I have to kill the process. Transitions to different levels seem to work properly. Any ideas?