If your SIM card hasnt been used for 1 month, It will have no network connection. Same problem with my O2 SIM for my Nokia 3100 Blue.
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If your SIM card hasnt been used for 1 month, It will have no network connection. Same problem with my O2 SIM for my Nokia 3100 Blue. Tried it with my dads Sony Xperia Z3, works.