19. Hi, you’ve reached [employee name]’s voicemail box. [Employee first name] no longer works for [company name]. Please call our main line at [phone number] and we’ll be happy to connect you with a current team member who can help.
After that, relaunch the app. This may fix the issue of voicemail not working on your device.

Open the Phone app. Tap the Voicemail tab in the lower right-hand corner of the screen. If Visual Voicemail is not set up on your iPhone, you'll see a button that says, Set Up Now. Tap that button. Enter, then confirm a custom voicemail password. Tap Custom if you want to create your own custom greeting when someone reaches your voicemail box.
The simplest, lowest-tech option—beyond operating a recorder while you blather over the speakerphone—is a cable: the Olympus TP-8 Telephone Pick-up Microphone for under $20. It doesn't digitally capture from your iPhone. Instead, it has a microphone built into the earpiece. Plug the 3.5mm plug on the other end into a recorder. Hold the iPhone up to your ear to talk normally. The TP-8 captures each side of the conversation from what comes out of the iPhone's ear speaker, while you can still hear the conversation.