Your title doesn't say about it, just says Kit Kat..
Anyways here is the manual for it on the Z1. If you don't find it on your device, it could be Sony Canada removed it. See if those steps gives u it.
EDIT - Just asked my buddy to check his Telus Z1. He said his doesn't have it either. Seems like it's a Sony Canada removal. Best thing to do Is contact Sony Canada Support and see if they can give you a answer. Rogers doesn't have a say if Sony removes something from the update.
According to other forums it's under Call Log -> Menu -> Enable Answering Machine. (I do not own a Z1 so I can't verify the info.)
He's back! Irish superstar Conor McGregor makes his return to the Octagon on January 18, and he's kicking off 2020 with a welterweight showdown against the man with the most wins in UFC history, Donald "Cowboy" Cerrone. Returning to action for the first time since October 2018 in the main event of UFC 246, the two-division champion from Dublin known as "The Notorious" one wants to make a statement against Albuquerque action hero Cerrone, who has picked up five post-fight performance bonuses in his last five bouts.