Anoying error with sim

[Windows Central Question]

i have a lumia 830 unlocked from at&t and is always saying no service i already tried with 4 diferent company simcard and all of them work except my sim and my sim worked on all phone i tried i have no ideas... and ive ready do a factory reset to windows 8.1 and nothing changed the sim

 

[libra89]

Try registering your phone IMEI with your carrier to see if that will do anything. That is a weird error but that's all I can think of.