Follow the steps below on how to disable calls from forwarding to voicemail on the Iridium 9505A

Solution: Disabling call forwarding

NOTE: You must be outside and registered to the network to cancel voicemail diverts.

1. Press "Menu" until you see “Call Related Features”, press "OK."
2. Press "Menu" until you see “Call Forwarding”, press "OK."
3. Press "Menu" and scroll to “Off”, and press "OK."
4. Press and hold "Clear" to exit the menu.