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

It's not going to be possible to get unlock codes because a t & t no longer has them. 

Those phones are unsupported. Have been for 4/5 years.  Just like any other old and unsupported phone AT&T no longer has unlock codes or cannot provide any help to get the phones unlocked . 

There is a long list of phones that cannot be unlocked from AT&T anymore. It includes iPhone 4S and older. The fire phone from Amazon. All 2G only phones, ant qwerty basic phones, The Razor phone , red hydrogen one , any phone by Panasonic, Sony, HTC , and any older Microsoft Lumia phones. 

They aren't lying. 

I don't think those phones will be allowed on any other US service provider. So there's no point in unlocking them. It's time for them to get new phones that are still supported and still have security patches available..

You can check the IMEI against T-Mobile's IMEI checker.  T - mobile is also shutting down its 3-g Network in June. If they won't allow the phones then no one will.  In which case unlocking them is pointless 

https://www.t-mobile.com/resources/bring-your-own-phone

In addition to the above, there is no such thing as “an old 3G plan that was just sunset”. Whatever plan they had also had access to 4G/LTE, all they need is 4G/LTE capable phones. Their old plan may well have been discontinued but they can keep that plan, they just can’t get it back once they give it up.

@sandblaster  since those phones were LTE for data, it was certainly not a plan limited to 3G issue.  Pretty sure the phones were kicked off At&t as they aren't capable of VoLTE (voice over LTE) 

The only old MS still capable are the 

 Lumia 640 XL and Lumia 950

I gig of ram and low storage, no security updates, and a 2015 phone.  

We can definitely share some insight about the 3G sunset @GrumpyGramps13!

As you may have heard by now, we have phased out our 3G network in February 2022. This will help us make room for an even better network that will improve your experience.

To ensure our customers are prepared for this change, we have helpful information that will answer some of the most common questions:

• How do I prepare if my phone isn’t supported?
  
  • Explore about current phones capabilities that are compatible to our network 
• How can you replace your device?
  • Upgrade your device online.

You can find answers to these questions and learn more by visiting our 3G sunset article.

We hope this helps, and let us know if you have any questions.

Ashley, AT&T Community Specialist 

@ATTHelp Ashley, I work in a large matrixed corporate organization and your response is a canned response that doesn’t actually address the question posed above.  It attempts to paint a roses picture instead.  I understand you’re moving on.  

But, how do they go about unlocking their phones?  They satisfy all the criteria but can’t seem to get their phones unlocked.  They don’t want to upgrade.  They’re on a fixed income.  

@GrumpyGramps13 read the posts other than the ATTHelp one.  They're not canned and answer your question in detail.

I want an answer from ATT.  That’s who my family has been doing business with.  That’s why I put it in ATT help forum.  

You've gotten the answer from AT&T.  If you want the same words rearranged, keep waiting, maybe you'll get it.  Or move on with your life.

@GrumpyGramps13 said

I want an answer from ATT.  That’s who my family has been doing business with.  That’s why I put it in ATT help forum.