Solution: Make it easier for callers to reach a real person. For example, if you have multiple phone lines, Spectrum Business Voice offers you the option of setting up an auto-attendant that answers your business phone and provides callers with a menu of options—such as particular employees or departments. This way, callers are more likely to reach the people who can help them. A hunt group is another voicemail feature: If one employee does not answer their phone, it redirects calls to another phone line in your business and can keep trying all the lines you have. It will only direct calls to voicemail if no one answers their line.
Other features such as Call Forwarding, Find Me, and Enhanced Voicemail ensure customers can always reach you, even if you're working remote.

You need to modify some settings of Skype for Business before you set up devices for an on-premises Skype for Business deployment. Ensure that you complete the following tasks: • Set the server log levels to capture only low-level events. For information on setting logging levels, see Set-CsUCPhoneConfiguration on Microsoft Docs.
It can be overwhelming to someone calling if your voicemail suggests they leave their name, address, time of calling, reason why calling, best phone number to call them back at, etc. They might not be prepared with all of the information and could end up leaving a confusing and flustered message. Instead, just kindly ask the person to leave their name and number and reassure that someone will be in touch as soon as possible.