I "locked" one of my SIM cards on my Android OS phone, now I cannot "unlock" it.

Whatevs

Commendable
Dec 6, 2016
2
0
1,510
A person needed to use their SIM card on a phone, I have two slots with two cards, so I take out one of my cards that I threw away cause I didn't need it anyway, and I put the new in, the "guest" SIM.Also, in my settings I block my remaining SIM card.

Anyway after that, I take out the "guest" SIM card, but now my phone won't let me "use" my existing SIM card, I cannot find any place in the settings to even address it.

Android ver. 4.4.2
Kernel ver. 3.4.67
 
Solution
The simcard you have in it is - blocked.
You may need to borrow one or take it to your carrier to add another sim card to it so that you can 'unblock' the blocked one.

Next time, just take out yours first.