Just clean any dust off inside or on sim card should work then
olga murgatroyd
November 2009
open the back, take out the sim card, blow on the open phone,,,there could be some little dust, put sim card, battery and back on. I have had this happen a zillion times with nokia.
jb
February 2009
I can answer this question...
my mobile phonesays insert sim card although sim card in phone already?
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