While there may be a native way to fix this I use and would recommend the free service youmail
YouMail Automated Secretary | Replace Voicemail with an Automated Secretary to Manage Your Calls
While they DO have paid plans all you need is the free plan. This service lets you get either text messages or emails when someone calls you, it provides you with an mp3 of the voicemail if they leave one, AND gives you details of the call AND can sometimes unmasked unknown caller IDs. It has many other features also such as custom messages for each contact, call screening, the ability to block any number or group of numbers (you can block all unknowns for example if you want). You can use the service via the web on a PC/Mac or your device OR you can use the iOS or Android apps.
