sims 3 bug wont change characters

@DakotahD14  It sounds like this UI issue:
https://sims3.crinrict.com/en/2011/10/bug-multi-selected-portraits.html

The advise to restart the game works in most cases; but I recommend to instead not save your game, and try to open a save from before the problem started. Do you use Save As or Save when saving your game? If you use the options to Save As you will have backup saves you made yourself that you can load, and see if the problem occurs in. This is also the recommended way to save for this reason.

If you only use the option Save, the game will still have created one backup save from the next to last time you saved. In that case:
Go to your The Sims 3 folder in Documents>Electronic Arts.

Delete the cashes. They are called:

CasPartCache.package
compositorCache.package
scriptCache.package
simCompositorCache.package
socialCache.package

Then open the Saves folder. There will be two saves with the same name (the one you have given it), for instance: SunsetValley.sims3; one of them will have the extension: backup. Remove that word ("backup"), and add a number before the: .sims3 in that save, so that it is now in our example named: SunsetValley1.sims3. You can now load that save from Main Menu. Directly make a new save by choosing the save option: Save As; name it Test. Exit the the game and delete the cashes in The Sims 3 folder again They should be deleted every time you have a problem, I delete them regularly anyway. Start the game and load the save named: Test. See if the problem is still occuring in the save. If it is I can give tips on what to do.