Voice mail notification is not going from Samsung Galaxy S23 Ultra

That's definitely odd. Are you using the visual voicemail app? If you'd like, our Mobility team could always look into your account to see if you've added it. If the original voicemail was deactivated (which can only be done by our Mobility team) it shouldn't be giving you notifications. One thing to note though is, if it was deactivated but you've since changed your plan, it'd automatically reactivate so you'd need our team to remove it again!