voicemail notification problem

[doox00]

Whenever I get a voicemail my mogul shows voicemail 1 unread, I go and check and delete the message but the phone will not remove the notification on my today screen, turn the phone off and back on and then will notify me again I have a voicemail, which I don't. After a couple days it will finally go away. Is there a way to fix this, annoying the crap out of me.