6-digit code sent to my phone or to my email

When I log into Turbotax on one PC, it will send the 6-digit code to my email . On the other PC, it will send the 6-digit code to my phone as a voice call, not text.  How is that? and how do I get  turbotax to send the 6-digit code to my phone as a voice call on BOTH or any other computer I use?