To delete a voicemail, open the voicemail app on your phone and select “Deleting voicemails.
Yes, you can listen to voicemails left by people on your phone. Just make sure that you have the voicemail app installed and enabled.
To reset your voicemail on your iPhone, follow these steps:
Navigate to Settings > General > Reset > Reset All Settings.
Enter your Apple ID and password and then click on Reset.
Your voicemail will be reset and you will be able to log in to your account to continue using your voicemail.