Do you have Voice Mails you want to save?
Can you open the Voice Mail app? Is there an unread message in there that you can delete?
Did you try to restart your phone?
No voicemails I want to save.
No unread messages to delete.
I've restarted my phone several times.
I've gone to Settings - Applications - Application Manager - All - Voice Mail. Cleared cache. Cleared data. Forced stop. Can't uncheck Show Notifications.
Try My Files>Device storage>VisualVoicemail
See if there is a Voice mail lingering, or click the file if there is one to see if it's lingering in there.
Yes. You'll also find a Voice Mail app, did you find it earlier when I mentioned it? Open that app also and click the left hand corner and make sure they are deleted and then look in deleted and delete those.