The basic rule of thumb is that callers should hear one of two things when they first connect with your voicemail — either an apology for not being able to answer the call or a “thank you” for having called. You can do both if you prefer, but keep it short and to the point.
11. “Hello! You’ve reached [company name] support line. We’ll be happy to help with your inquiry. In the meantime, have you checked out our [website, help forum, etc.]? It may have the answer you’re looking for. If not, leave your name, number and reason for your call. We’ll reach out to you within the day. Thanks for calling [company name].” Sometimes, a caller likes to find the answer to their own questions. Let them discover by directing them to your website or help forum if you have one.

And be sure your email is as impactful as your call — You can use these essential email tools to make sure your cold email pitch is as perfect as your first voicemail outreach.
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.