The prompt will stop appearing. If the 611 Automatic System does not work for your carrier, you can head to your carrier‚Äôs official website if youriPhone 6s keeps asking for voicemail password. From the myWireless Account home page, select Phone/Device then choose the Reset Voice Mail PIN link from the left column. Note: If there is more than one line on the account, make sure the correct wireless number is displayed in the Wireless Number list before selecting Reset Voice Mail PIN. To reset the password for any of the lines on the account, choose a wireless number from the dropdown menu and click Submit. In a while, iPhone will display "Password Incorrect - Enter Voicemail Password." Enter the last seven digits of the wireless phone number and tap OK. Log into My Verizon with your cell phone number and password. If you've set up a username, use the username instead of your phone number. Select My Verizon> Reset Voice Mail Password. Choose your cell phone number from the drop-down menu, and thenclick on "I Will Create My Own Password." Enter and confirm your new password. Click on "Submit" to save the change. Sign in to My Sprint with your username and password. Click“My preferences” tab. Under Things I can manage online, click on Change voicemail passcode. Enter your new passcode and confirm. Tap Save and you will get a message informing you the new password has been saved.
Website: https://www.cellphones.ca/answers/how-to-listen-to-voicemail-from-a-landline-phone/

You can do so by logging in to your carrier’s website or contacting customer service for assistance. Some network providers also let you do so via their mobile app. Go to Settings → Phone → Change Voicemail Password.Enter the new password.
Android phones can access voicemail by holding down the 1 key on the dial pad until the phone dials your 10-digit phone number. You will automatically connect to your mailbox and be prompted to enter your temporary password; this password is the last 4 digits of your phone number followed by the # key. Start the Google Voice app. Tap the three horizontal lines at the top left of the screen (sometimes called a hamburger menu), and then tap “Settings.” In the Voicemail section, tap “Voicemail greeting.” Tap “Record a greeting.” How do I access my voicemail? To call your voicemail on an Android phone, simply open your phone’s dial pad and hold your finger down on the “1” key. You can also call your voicemail from a different phone by calling your own number and tapping the pound key. How do you check your voicemail?