Did you try it multiple times? As shown in the video, it is not guaraunteed to encounter an error and the part I cut out involved me joining and leaving the menu more than 10 times before receiving an error. It depends on how lucky you get.
Secondly, no, I do not have another script controlling the cameras. If you are talking about scripts I made, the menu one is the only one.
Ultimately, dont feel guilty if you cant find the reason for why this error is happening. I can find a workaround or partly axe the feature as it is not a vital part of my project. Perhaps the root of my problem is just the fact that im using tweens.
My bad, I thought that I found the problem but I was wrong. I tried your code and it works well for me, with no errors thrown in output, even when running closeMenu and openMenu multiple time in a row.
Is the Player Module the latest version?
Other than that, I don’t know. It could be a new random bug due to a recent update. Try reporting it in #bug-reports (if you have access)