Does anybody know how to get an iPhone to remember that it is in Canada again after returning from the U.S.? When I cross into SK from North Dakota, it has given me a no service indication twice. Repeated network resets, power-downs, and removal of the SIM card do nothing. The last time, it simply started working again for no apparent reason. Tired of this, can't even call Telus to ask them, stuck using Tim Hortons wifi.