How get to unlock screen without SIM

[stocktiki]

Just got the unlock code from my carrier (Cricket) for my Lumia 640. I'd like to unlock it - without removing the SIM and putting in one from another network.
My old Lumia's always let me enter ##782# - to get to the unlock screen - from which I'd enter the unlock code. But this command doesn't seem to work on the Lumia 640.
Anyone know of another way to get to the unlock screen?
Thanks!

 

[libra89]

Wait, I don't know if that is possible (but not sure). What was your old Lumia(s) running? It could be different with lumia denim?

 

[geekfiredog]

The correct code to bring up unlock screen is ##7820# - you missed out a "0" in the code.

Got these codes from another forum
*#06# to retrieve the IMEI
##634# for color variant + life time counter
##7820# for unlock menu
##3282# for field test menu

 

[LumiaGuy]

With my Lumia 520, when I enter ##7820#, the screen shows a unlocked padlock and the box below to enter text in does not respond to bring up the keyboard to enter text. Am I doing something wrong or is my phone already unlocked?

 

[stefanorickeets]

With my Lumia 520, when I enter ##7820#, the screen shows a unlocked padlock and the box below to enter text in does not respond to bring up the keyboard to enter text. Am I doing something wrong or is my phone already unlocked?

It's already unlocked.

 

[LumiaGuy]

It's already unlocked.

That's strange because I never have requested a unlock code since buying the phone a little over two years ago. It's an AT&T Gophone and that's the only carrier I've been using it with.