Voice Mail to email not working

Sometimes when my voicemail picks up a call it will not forward to my email. That is how I check in on messages from a remote location with my cell. I am sitting in my office now and have listened to two messages and yet they did not show up in my email.Is there a way to check this  to make sure I have the setup correct or is there a problem within the system I should be aware of. Being a service tech. it is important I am able to check my incoming calls quickly