Tap and hold Disconnect until your mobile phone is turned on.
If you're asked to key in your PIN, do so and tap OK. The default PIN is 0000.
If an incorrect PIN is entered three times in a row, your SIM will be blocked. To unblock your SIM, you'll need to key in your PUK. The PUK can be obtained by contacting Customer Service. Please note: If an incorrect PUK is entered ten times in a row, your SIM is blocked permanently. In this case, you'll need a new SIM from Optus.