So my wife mentioned she had issues with her iPhone voicemail's. A few people mentioned they had left voicemails but Katie never received the voicemail's. Turns out her voicemail had not worked for about a month! Any way after searching the internet figured out her issue and resolved the issue. Below is the solution
go to settings, general.
scroll down to see if you have something called, "profile".
if you do, click on it. then REMOVE IT!!!
then RESET NETWORK SETTINGS.
