Phone randomly gives me ' NOT REGISTERED ON NETWORK ' message when i try to make calls. it's done this once before, i called att, no luck, was driving to the store, and it decided to work again. i am in full service where i am right now, but it won't make one call. it's worked all day long, no problem. when you go to status of phone (menu,settings,about,status) it says i am NOT on any network..then, all on it's own, it will go back to being on the ATT network. wanting to know if anyone else has had this issue, and how it was resolved, if it was. Thanks, in advance, for helping me with this!:hello:
I have had this before with a few phones. You might need a new sim card. That's is what i had to do. Seemed to fix the problem for me.

Especially if you swap your sim between phones.

The sim cards can go bad. Might try it.