Some iPhone 5 users are turning to support forums to find a fix for an alleged glitch with the new SIM card that causes the device to suddenly stop working.
The users say they are unable to make calls or connect to a cellular network after the phone abruptly displays a message "No SIM card."
One user has started a thread on the support forum titled "iPhone5 'NO SIM CARD INSTALLED' 'NO SERVICE.'"
"I'm in various places like a restaurant or my home and I get the same issues," she said on the thread. "Why does this happen? I cannot live like this coz I have no landline."
The problem appears to be spread across the three major U.S. networks -- AT&T, Verizon and Sprint.
Users are helping each other find solutions in the forums, with some suggesting the affected owners update their iTunes software to the latest version and re-sync their iPhone 5.