Voicemail default greeting

No I'm trying to get the default voicemail greeting to play without recording any greeting myself.  The current default voicemail greeting is not saying my phone number like it should🤔

Sorry, I don't have Cox phone so I can only go off what I find on google. How about this? Step 5 and 6 seem relevant. Seems you can record your number instead of your name in the greeting.

As usual these voicemail instructions don't work.  If I record nothing for 2 seconds like it says I still can't get the default greeting to play properly.