Website: https://docs.microsoft.com/en-us/skypeforbusiness/deploy/deploy-enterprise-voice/configure-voice-mail-escape#:~:text=To%20configure%20voice%20mail%20escape%201%20Start%20the,can%20range%20from%200%20milliseconds%20to%208000%20milliseconds.
Before you officially pick a greeting, why not practice on making your voice even and understandable? I know that my voice rises when I speak on the phone, and I tend to speak faster, so I practice in the mirror to slow down my voice and make sure that I am speaking as naturally as I can.

I have a confession to make: I haven’t recorded a new voicemail greeting since 2014. In the past four years, I (hopefully) have become more articulate, poised, and self-assured. But hear my voicemail recording, and you’d think I was still new to the work world, a little unsure of myself — and probably not an authority. Obviously I need toupdate it. And if you haven’t changed your voicemail greeting in over a year, you’re likely in the same boat. After all, a professional voicemail recording boosts your credibility, makes you seem more competent, and encourages whoever’s listening to it to continue the relationship. A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction. With that in mind, I’ve written 18 unique voicemail greetings for every situation. Pick your favorite, practice a few times, then record your new voicemail.
Once you thank your customers for calling, state your name and the department. Make sure to speak clearly so the caller knows they called the right place and can understand what is being said. Don’t rush through in case the caller wants to write the information down.