Power off, check SIM orientation, restart, and verify carrier compatibility.

Power off the device before removing or inserting the SIM card.

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As for the nanoSIM card, it should be put in the right way around.

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Not having inserted the SIM properly can lead to non functioning of it.

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Make sure you put back your SIM into its original phone.

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Using a different phone for using one’s SIM card may cause problems due to compatibility.

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iPhones that have carrier locks may need unlocking if another SIM is used.

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Contact your initial vendor for unlocking your network lock.

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Check SIM card functionality if issues persist after reinstallation.

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