Sims 4 Calendar glitch after update

@Ramcam7  If no one knows which specific mod is causing this, or you don't want to wait for an answer, you can use the 50/50 method to quickly test all your mods.

https://modthesims.info/wiki.php?title=Game_Help:Finding_Problem_Custom_Content#The_50.25_Method

It's unlikely that custom content would cause this issue, so you can set aside your cc for now and only test it if your mods come up clean.

did you ever find the mod causing the issue?

No, haven’t found the issue yet and I’m slowly going through my mods folder doing the 50/50 method as stated above, since it seems that’s the only fix

I have this issue where it has shown through Better Exception that it is to do with custom holidays and mods such as SNB financial Centre, Real Estate, Basemental mods and Lot 51 doorbell mod is listed as possible mods that could cause this issue. Though the same last exception has generated upon removing all mods. I have reset my sims 4 folder, repaired the game, started on a new game save and had the same issue.I then went into the calendar and deleted any custom holidays planned by me. The calendar would not open the edit menu for these custom holidays and would not let me use the UI without hitting 'Esc' to exit the greyed out screen. Im not sure whether this was because the holidays I've planned use custom icons from Zerbu or the fact that they are not game generated holidays. It did allow me to edit the game generated holidays but lagged showing a loading wheel for 20-30 secs before opening the edit screen. I hovered over some days with the light festival scheduled, and it has listed around 6 light festivals in one day at different times.

Another issue I have, which seems triggered with the LE's thrown by this error is complete lag and freezing of sims or the screen freezing with sounds of the sims still active but no movement on the screen with them in it and then soon after, my laptop freezes where I can not access any other app on my mac, the screen blacks out and then I am thrown to my mac's user login screen, and upon logging back in, The Sims is shut down with no crash report in the game folder. I then try to reopen the game and then Origin no longer works either saying it is being used by another user and to ask them to close it down in their profile; mine is the only profile (admin) on the mac, or it says that origin is not installed.  I then have to restart the whole computer. I have also re-downloaded and installed origin again. 

I know for sure this issue has only developed since updating to the new werewolves patch. This desperately needs fixing in the next patch as it had deemed the game unplayable.

@tishagb  You really need to test without your mods.  A number of mods are incompatible with the most recent patch (1.89), and you'll need to remove or update them.  This is not a game issue—Sims 4 is updated once a month or so, which is normal and a good thing.  Without updates, or with only those updates that didn't conflict with existing mods, the game wouldn't get any new features or support for any new packs except maybe some kits.  The side effect is that mods break, but that's a small price to pay.

I am a long time player all the way back to the urbz so know how The Sims franchise works. I have tested in all ways including 50/50, 20/80, 1/99 and no mods at all. This problem is most definitely a glitch since the update, i believe impacting saved game files. I was using the same game save just fine before this update and have updated all mods so far, this being confirmed by the same game save throwing LE's and a faulty calendar with all mods removed.