Hi all! I'm going to assume it's just because it's a 420 model and I can't change the 2nd button but I'll ask anyway. I'm trying to set up the 2nd button to monitor another extension but nothing shows up on the phone, it just acts like another call appearance button. I'm able to successfully save the change to the button with no errors but it doesn't change. I have even tried changing it to a Page button but still it doesn't change. Is it because it's only a 2-button phone?