Creating a voicemail greeting might not be fun, but with the scripts I’ve shared, you should have an easier time. No need to practice time and time again — simply plug in your name, company title, and other details, then read it out loud to your phone’s voicemail greeting recorder. With a professional greeting, you’ll continue nurturing prospects even if you don’t pick up the phone.
Press # key or hang up after recording greeting, you can view and manage the greeting in Greeting Management tab. Record or upload voicemail greetings for a group voicemail Upload a group voicemail greeting Log in to PBX management portal, go to Call Features > Voicemail > Group Voicemail, edit the desired group voicemail. In the Group Voicemail Greeting section, click Greeting Management. In the pop-up window, click Upload. Select an audio file to upload.

You can also upload an unavailable greeting using the OnSIP app. After logging in, click on the Voicemail Settings gear icon at the far right. Make sure that the Custom Greeting is toggled to "on." You will then see an option to upload a .wav file of your choice. This recording will serve as your unavailable message.
A word of warning: These greetings will not do you any favors if you're in the midst of a job hunt or work in a conservative industry. Always remember your target personas. If there's a chance they won't appreciate your sense of humor, opt for a straightforward greeting instead.