If you want to add another condition to your rule, select Add condition. You can add multiple conditions to a rule but do this judiciously so your rules don't become overly complex.
How how how can that be??!! This is the year 2016, and I can’t set basic options like the number of rings! Actually I too want to turn off voicemail completely. I am aghast to read I don’t have a choice.

I am and have been trying to set up voicemail for my iPhone 11 purchased at the Waycross store. This is not working for me. I got to the screen where I put in my password and where I was to set up a greeting. There were no instructions past that. I recorded a message but never heard a beep or confirmation that my voicemail greeting was complete. I have tried several time in succession to try and play the message but nothing happens. i just have greeting in the top left and when i record it and save it does not offer a voicemail message for a caller when someone calls
New voicemail & password setup. Make sure to set up your voicemail within 60 days of activation or it’ll be automatically removed from your account. From your wireless phone, press and hold 1 or the Voicemail key. Select your language preference. Create a 7 to 15-digit password. Select your preferred greeting.