Visual Voicemail won't let me play back or adjust greeting
My Iphone 6 uses Verizon. I successfully changed VM greeting a couple of days ago then tried to change again the same day but none of the VM greeting buttons would work except cancel.  Called Verizon and they had me reset all settings. Still didn't work. The told me to re-set network settings and still didn't work.  The referred me to apple and I did a did a back up and restored using by back up.  Still didn't work. They wanted me to try to restore as new without the backup which I was reluctant to do. 

Just deleted VMs and Delted VMs, and (for now) I'm able to record and change my VM greetings.  Thanks Kal-al