Too late at night; prepay, sono bill; 'Settings- phone- number'= no number. Also 'Contacts'- no number.
Weird and annoying.
There is a code [*6779#] or similar to enter- don't know what it is!
What I did was to get my ZTE speed download Talkatone then type in your home phone number or a number you used to have then type it in then it would tell you all the numbers you had currently or a long time ago then you choose it then your number is back