Unlock sim after passing opportunity to unlock on iPhone startup

This must be some basic stuff but I'm unable to figure it out.
I've restarted my iPhone, inserted my security code and then when the numpad appeared to insert my SIM pin code, I pressed the home button and now I can't trigger that numpad again to insert my pin code.

The only thing I see is Locked SIM in the upper left corner and can't do anything about it.

The question: How can I trigger the panel to unlock my SIM card again?

Solution 1:

On iOS 10, go to Settings > Phone > SIM PIN to unlock your SIM.

On iOS 15.1, go to Cellular, select the plan, and SIM PIN should be the next-to-last option on the second group (before Carrier Services, after SIM Applications).

You can also disable the SIM PIN on that screen.

Solution 2:

Turning the Airplane mode on and off also shows the dialog again.

Solution 3:

Note that on the iPad (the model with a SIM card option) the setting for unlocking the SIM is under Settings > Mobile Data > SIM PIN.

Solution 4:

You can also place a call, the phone will show the unlock question again.