@Sophieking2004 Just to clarify, after removing and adding the job with MC, did the time until the work shift ever diminish? It might say "starts in 2 days" at the beginning, depending on that job's work hours; I'm wondering whether the sim could eventually go to work at all.
If the time until work never decreased, please try the MC method again, except this time, quit the game after you use "remove quit careers" and before you give the sim their job again. In fact, do this with at least two different sims. You can use "save as" to rename the save so your original remains intact under its previous name. After quitting, delete the five cache files in your Sims 3 user folder:
- CASPartCache.package
- compositorCache.package
- scriptCache.package
- simCompositorCache.package
- socialCache.package
When you reload, give one sim their job, but for now, don't increase their level. Give another sim a different career, preferably one that no other sim in your current household has had. Let me know whether either sim eventually goes to work; like I said, it might take a couple days.
You can also try the above along with deleting the rabbithole lots where the sims should work: delete them before quitting and don't place them again until after you reload.
Another thought I had was that perhaps a holiday is stuck, whether one of the Seasons holidays or someone's high school graduation (from Generations). If you think this may be the case, or if this problem started immediately after a holiday or graduation, let me know.