In addition to protecting your Android Phone with Face ID and Lock Screen Password, it is really important that you remember to enable the SIM Card Lock on your mobile device.
As you must be aware, the SIM Card contains information about your phone number, billing information, Contacts and other data, which can be easily misused.
Hence, it is really important that you lock the SIM Card on your Android Phone by replacing its current default PIN (setup by the carrier) with a New 4-digit SIM PIN.
Enable SIM Card Lock on Android Phone
Before going ahead with the steps to enable the SIM Card Lock on your Android phone, make sure that you know the Current PIN or the Passcode for your SIM Card.
If you did not change the SIM PIN, it is likely that your SIM Card is still using the default SIM PIN, which was setup by your mobile service provider.
Note: Do not try to guess the PIN, as you may end up with a blocked SIM Card, in case you enter incorrect PIN 3 times.
1. Steps to Enable Sim Card Lock On Android Phone
After finding out the default or the current PIN for your SIM Card, you can follow the steps below to enable SIM Card Lock on your Android phone.
1. Open Settings > scroll down and tap on Lock Screen and Security.
2. From the next screen, go to Lock Screen and Security > Other Security Settings > tap on Set up SIM Card Lock option.
3. On the next screen, move the Lock SIM Card toggle to ON Position (From Grey to Green).
4. On the pop-up, enter your current SIM PIN and tap on OK to enable SIM Card Lock on your Android Phone.
2. Change Default PIN of the SIM Card
If you are still using the default PIN for SIM Card, it can be easily unlocked by anyone who knows the default PIN used by your mobile service provider.
Hence, the next step is to change or replace the default SIM PIN on your Android phone with a new 4-digit SIM PIN.
1. Open Settings > scroll down and tap on Lock Screen and Security.
2. From the next screen, go to Other Security Settings > Set up SIM Card Lock > tap on Change SIM card PIN option.
3. On the pop-up that appears, enter the Current or Default SIM PIN and tap on OK.
4. On the next pop-up, enter your New four-digit PIN and tap on OK > On the confirmation pop-up, enter your New PIN and tap on OK.
5. After this, use the Power Button to Power OFF your device.
Now, when you restart your device, you will be prompted to enter your New SIM PIN.
How to Unblock SIM Card
As mentioned above, the SIM Card installed on your Android phone can get locked, if you try to guess the PIN and end up entering an incorrect PIN three times.
If this happens, you should be able to unblock the SIM Card by logging in to your mobile service account and locating the PIN Unlock Key (PUK) associated with the SIM Card.
1. Login to your Account on the Mobile Service Providers website.
2. Locate Unblock SIM Card option and click on it. This should open a new window containing the PUK Code associated with the SIM Card.
3. Enter the PUK code on your Android Phone and create a new PIN.
Note: Entering an incorrect PUK code too many times will result in the SIM being disabled or permanently locked. If this happens, you will be required to get replacement SIM card from your Service provider.