As I mentioned earlier, one of the common reasons why an iPhone won’t play voicemails is because the Phone app isn’t working properly. Closing and reopening the Phone app allows it to “shut down” and start again, which can sometimes fix a software glitch.
When using the T-Mobile Visual Voicemail app, for example, select “Settings” from the three-dot menu in the upper right corner of the screen.

5 hours agoThe default voicemail greeting on the iPhone plays generic Your call has been forward to an automated voice message system recording. If you use your phone for work, create a personalized greeting that tells people you're a professional. If your phone is for personal use, create a personalized greeting so people hear your voice and know they called the right number.
If you had a generic voicemail greeting and recorded a personalized voicemail greeting you can change to the custom voicemail greeting by saving your custom voicemail recording. You should first listen to your recording by playing it from the menu and can then choose to keep the custom greeting or revert to the default one. Don’t forget to confirm your changes by tapping “Save” when done. How do I change my voicemail message on Samsung?How do I delete my voicemail greeting on Android?How do I change the default voicemail on my Android?How do I manage my voicemail on Android?How do I change my voicemail greeting?How do you use voicemail on Samsung?How do I remove a name from my voicemail greeting?How do I turn off my voicemail message?How do I turn off voicemail on Samsung?How does voicemail work on Android?What is my voicemail PIN?What is the best voicemail app for Android?How do you unlock voicemail on Android?Is there a voicemail app for Android?Does Samsung have a voicemail app? On Android devices above Android 5 (Lollipop), open the Phone app. Then, press and hold “1” to call your voicemail. Now, enter your PIN and press “#”. Press “*” for the menu. Press “4” to change settings. Press “1” to change your greeting. Tap the three dots (upper right corner of screen) Tap “settings” Tap “voicemail” Tap “advanced settings” Tap “setup. Tap “voicemail number. Enter your 10-digit phone number and Tap “OK. Tap the home key to return to the main menu. Open your device’s Phone app ​. At the top right, tap More . Tap Settings. Voicemail. You can: Change what handles your voicemails: Tap Advanced Service. Set up your voice mailbox: Tap Advanced Setup. Change your notification settings: Tap Notifications. Open the Google Voice app . At the top left, tap Menu Settings. In the Voicemail section, tap Voicemail greeting. Next to the greeting you want to use, tap More Set as active.