If you are calling my cellular phone, and your phone number is not in my contacts, then the phone call will be sent to voicemail. This is done automatically, and rarely will I disable this feature, and even if I do – it is only for a short time when the need arises. This is device level, so if my cellular phone has 2 telephone numbers, then both numbers will have the same rules. As for my home phone, it is likely that I am just not answering calls at the time. Obviously, if you call my voicemail number, you will reach my voicemail box every time you call that number.