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GrumpyGramps13's profile

New Member


6 Messages

Thursday, April 14th, 2022 6:25 AM


How to unlock my Mother's and Aunt's Lumia 640's

I'm trying to help my mother (76-yo) and aunt (79-yo) unlock their Lumia 640's.  They have been ATT customers for 6-years and 8-years respectively and had an old 3G plan that was just sunset.  However, when they tried to get unlocked, ATT first stated they couldn't confirm that they were purchased from ATT.  They protested as they have the original boxes and the receipts.   The agent instructed them to go into the ATT store and show them so the store could verify the receipt.  The store agent said they can't do that but offered to enter the info into the portal.  However, when checking the NUL cases, the unlock was denied.  I spoke to tech support on their behalf for an hour on Monday and they got the unlock approved by their manager and entered a case, CM20220411 and stated it would be 24-72 hours and that I would receive an email (yes I provided my personal email).  My mother received a "free text message" from ATT yesterday stating unable to unlock and to call customer service at 800-331-0500.  The agent told them they don't have the unlock codes for the Lumia 640 as they deleted the whole dataset.  (Edited per community guidelines) is that, are you serious or what?  My mother and aunt have been good ATT customers and they're just getting a runaround.  How do they unlock their phones?  

ACE - Sage


110.9K Messages

1 year ago


It does not matter that the phones are paid for years ago, or that they are eligible for unlocking. AT&T is under no obligation to unlock them, but does so if they can possibly provide you with an unlock code. Unfortunately you waited years too late to do this. Unlock codes are no longer available for unsupported devices. 

You did already receive an official response  

"The agent told them they don't have the unlock codes for the Lumia 640 as they deleted the whole dataset." 

This was true. Unlock codes and any other information for unsupported phones is deleted from AT&T records.

If your mother and aunt switching to a different service provider, switch to one that gives them a free new phone. Even some of the cheap prepaid services provide you with an inexpensive prepaid phone just for signing up for their service. Anything you get is going to be more updated, faster response, and more storage than the piece of garbage but they are using now. The lumia 640 is so ridiculously outdated it's laughable. 


Community Support


221.3K Messages

1 year ago

 @GrumpyGramps13, we're here to answer all your inquires about AT&T services.


Wonderfully stated @formerlyknownas, @sandblaster, @JefferMC, the Lumia 640 is no longer supported. 


Submitted an unlock request that has been denied and you are unsure why?

  • To unlock a Prepaid device, the device(s) must be compatible to our network 
  • Your device isn’t reported lost or stolen, or involved with fraud.
  • Your device isn’t active on another AT&T account.

Check out some of the great AT&T Prepaid Offers today


  1. Sign in to MyATT and select upgrade device (On the app, the upgrade option appears on an eligible device)
  2. Choose the device you want to upgrade (The device ready to upgrade will have green text)
  3. Select phone or wearable
  4. Select your new phone
  5. Follow the prompts

Thank you for reaching out to Community Forums.


Ashley, AT&T Community Specialist 



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