Best answer by Mohammed
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If your SIM has been secured with a PIN, you will be asked to enter the PIN anytime you place the SIM in a different device. If you enter it incorrectly three times, your SIM will automatically be blocked and you'll be asked for a PUK (PIN Unlock Key)"
You can get a PUK from one of their 'Live Chat' agents on their website. (https://www.idmobile.co.uk/).
The link for this topic is here: https://community.idmobile.co.uk/ask-a-question-18/blocked-sim-card-186
Please get in touch with us so we can provide you with a PUK code.