stinaxx03 The sims showing the same name is a known mod-related issue:
https://answers.ea.com/t5/Mods-CC-Issues/MOD-RELATED-Sims-all-get-same-name-in-CAS/td-p/13907952
Please try the suggestions in the accepted solution on page one of that thread, including the link to the thread about custom preferences.
If that doesn't help, remove your entire Mods folder and test again. You don't need to save your progress; the point is to see whether you can take this sim into CAS at all. If this works, use the 50/50 method to figure out which mods or cc items are causing the problem.
https://modthesims.info/wiki.php?title=Game_Help:Finding_Problem_Custom_Content#The_50.25_Method
