SIMcredible!Feb 22, 2018

Hello ʕ • ͡ᴥ • ʔ

Sorry for the delay in answer you. We were under summer vacations.

Need to know these answers, please:
1- Is your game fully patched?
2- Did you redownload the mirror from TSR?
If yes, are you sure you have only the newest version of the mirror installed on your Mods folder? (if you have both old and new, the game only reads the old broken one);
3-If yes, I need you to fix the files yourself.
Fortunately the fix is easy, free and quick.
You can choose between Sims 4 studio or TSR workshop to fix. Both tools are free and easy to use.
Here are the steps :

using Sims4 studio:
1- Create an account (it's free) to download the Sims4Studio newest version
http://sims4studio.com/thread/562/sims-studio-windows-wishes-open
2- Install it.
3- So go to menu Tools - batch fixes - objects - Fix mirror tunning - run
4- Wait a bit (it can delay due to the size of your Mods folder) and click OK.

or using TSR workshop:
1- Download the newest TSR workshop version
www.thesimsresource.com/workshop/
2- Install it.
3- So go to menu Tools - mirror batch fix - OK
4- Wait a bit (it can delay due to the size of your Mods folder) and click OK.

Wish you have a great time with your sims ◕◡◕