Open Phone → Make sure you are on Keypad → Press and hold the number 1 for a few seconds. It will call your voicemail; You can check your voicemails here. 3. Force close and reopen the Phone app. To force close Phone, on iPhone X and later swipe up until you see the apps in task view, then swipe up again on Phone.
This guide will show you how to change the iPhone voicemail message on iOS 9. Even if you don’t use the iPhone for calls very often this is a great thing to do, since you may end up sending more calls to voicemail.

8. "Hi, you've reached [your name]. I'm unable to come to the phone right now. But if you leave your name, number, and a short message, I'll be sure to call back."
Creating a professional voicemail greeting isn’t complicated, but you need to keep a few things in mind to ensure success. The following tips will help: Be friendly and welcoming - let your company's personality shine!; Have a clear voice, speak at a slow to moderate pace, minimize background noise; Ensure the greeting is human and approachable; Keep the greeting short and informative; Ensure the greeting doesn’t sound robotic or unnatural; Show your gratitude for the call by saying thank you; Manage expectations by clearly stating when the client can expect a callback.