Voicemails need to maintain a professional consistency that’s aligned with the entity it’s representing. That said, the structure can vary depending on the situation. There’s no template set in stone. In fact, trite and generic should be off the table. The goal should be a balance of uniqueness and practicality.
The telephone systems have the feature named as Voicemail. VoIP is the best example of it. When a receiver is unable to pick up the phone, then the caller can leave the voice message on the receiver’s phone. In older telephonic machines, such messages were stored as a voice message directly, and the receiver can hear them later. In modern telephone systems, such info is being stored on the server of the service provider in the user’s mailbox. It is similar to email in which the messages are saved in the form of audio instead of text.

You can record custom messages right from your dashboard using Dial-and-Record, which allows you to record it through your phone. Then, once they’ve been recorded, they’re saved in your account to be placed in any section, such as for the welcome greeting, menu prompt, or voicemail greeting, in addition to other sections. Enter the number of rings between 0 and 9, or press #. If you choose 0, calls will go straight to your voicemail without ringing first. If you choose # calls won't go to voicemail at all. The phone will ring until you answer or the caller hangs up. Follow the voice prompts.
Did not work for me. They all come back the next day even after I permanently delete them