When "Extension A" leaves me a voice mail, the voice mail says I have a message from "Extension B". As far as a I know, I am the only one who has this problem with "Extension A" calls. However, another person has the same type of problem with "Extension C" and "Extension D", while no one else has that issue. It is odd. First, do we know what causes this issue? Second, do we know how to solve it?