If your carrier supports the iPhone voicemail feature, you can retrieve and listen to your voicemail right from within the “Phone” app and call your contacts back by simply tapping their messages. That type of functionality is pretty neat and useful, because it saves you actual time. If not supported by your carrier, you will not be able to see the visual overview of your voicemail inbox and use any of the related features. Tapping the “Voicemail” tab in your “Phone” app will simply call the number associated with your voicemail box. So let’s get going with creating our custom voicemail greeting on iPhone! How to record your own Voicemail on iPhone Phone → Voicemail → Greeting → Custom → Record → Save
Call the voicemail system to change your password: From your AT&T wireless phone, press and hold 1. For AT&T Wireless Home Phone, dial 1. If prompted, enter your voicemail password. If you have new messages, press the * key to skip to the Main Menu. In the Main Menu, press 4 for Personal Options. Press 2 for Administrative Options.

1. From standby mode or the Phone application on select Sprint phones, press and hold the Envelope key on your phone until the display reads Connecting… (your Sprint phone number), or press and hold the 1 key until the display reads Connecting… (your Sprint phone number).
5. Switch on and switch off Airplane Mode. You can do this from either Settings or the Control Center. On iPhone X or later, swipe down from the top right of the screen (where the battery indicator is).