On an iPhone XR running iOS 13.2.3 and connecting to the mobile phone network using a number supplied by Three, how do I disable voicemail?
I have never actually configured voicemail, but whenever someone calls my number and the phone is switched off (which is most of the time), they hear a message giving them the option to leave a voicemail. I want the number to keep on ringing without being answered, or if they must hear a message then for the message to tell them the phone is switched off and that's it.
Recently I got a text message from Three itself saying they'd left me a voicemail, and I would like to delete that voicemail without setting up voicemail in the first place.
In short, I would like to kill the voicemail facility, deleting whatever may be in the box, without even listening to it and without setting up voicemail in the first place. How can I do this? If to kill it properly I need to set it up first and then kill it, how do I achieve that?