Change Number of Rings Before Voicemail

Xfinity is by far the best company in my area, and for that of family in other states of America. 

My problem with Xfinity Assistant, Xfinity Live Help, and others responsible for continuing customer service is unnecessary in this day and age. I simply want my Xfinity purchased iPhone to pickup voicemail in less time/rings than 30seconds/15rings.

Used Xfinity Assistant...dead end (There are no canned questions that match my need.)

Used Live Help...dead end (Agent did not know how to help me...sent me to APPLE, Inc)

Apple Inc...dead end (Sent me to [Edited: "Personal Information"]...dead end)

Then... I 

>>>>>>>>>>>>>>                      Opened my iPhone looking under settings, and Carrier and found this number [Edited: "Personal Information"]            <<<<<<<<<<<<<<<<

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

An Agent answered the call, then called Mobile Voicemail Support for me, while I waited (Some time Later... ) -Complete! Win! Thank you Javier and unknown tech!

So...while I wait, let me explain something most people do not know. 

The systems that allow moves and changes is usually a computerized telephone system. It requires both permission to access and permission to change (with a paper trail). A tech will access the associated number/device/owner and simply enter a telephone system command to make the change. Usually, they want the owner (me/you) to verify the change happened...that's it!

So, before I could even finish the above paragraph, Javier and the unknown tech changed my rings from high to low -before entering the voicemail system.

CHECK YOUR SETTINGS/CELLULAR/CARRIER SERVICES/XFINITY MOBILE CARE > [Edited: "Personal Information"]