Help get my, & my sisters "AT&T GoPhones" unlocked- we have each had our prepaid accounts with AT&T since our purchases back in 2015 & 2016

I have tried to get help from At&T tech support to have our cell phone service changed to another provider by unlocking our At&T GoPhones (Lumia 640 Microsoft phones). AT&T did a "network upgrade" in Mid-March 3/12/22 & our model phone was dropped from AT&T's new "network".

1st, we could no longer use our cell phones to get in touch with AT&T prepaid to find out why our phones service stopped -not able to receive or make calls.  We had to borrow a land line to make multiple calls to AT&T... this was because the persons in the prepaid dept. did not know why we didn't have cell service, they finally figured out & said the "towers were being worked on in our area" and "that we would probably get our service back soon."

Since 3/18/22 I've talked to many: Chris,Philip,Abbey,Reyn,Shirley,Camillo,Alex,Brandon,Ruben,Amy,Jackie,Omar,Jason,Rose, Juan-- and several others!  I've waited on the borrowed land line while the folks at AT&T put us on hold (sometimes dropped our call) & trying to figure out what to do about us not having any phone service (even though we were each "paid up" on our individual auto-pay plans since 2015 & 2016 through the end of March 2022. Finally, a man named Alex (thank you) in tech support, on the 30th of March, asked me/us to power down & take the back off both cell phones and give him the IMEI #'s and from that info he said, "your phone models are no longer supported by the AT&T network". He transferred me to another department to get a "replacement phone"- I waited another 10-15min and a recording said, "the Reward Center is closed," "please call back between 9am & 6pm central time M-F." I did call back the next morning, but that man said "his dept. no longer handles Replacement Phones", and that I needed to call a different department... which I/we did and that person explained that in order to get a "replacement phone" I needed to keep our accounts open by having another phone temporarily till the other phones arrive in 7 to 10 business days by mail... that was when I asked to get both of our AT&T GoPhones UNLOCKED.

This saga continued:  Several "Unlock Request Tickets and Cases" were started and ran their course for 24 up to 72hrs & even  4 days - to no avail...!

I was told by one of last the tech persons I talked with, to take the original purchase receipt and our original boxes(which I have kept these 6-7 years) to an AT&T store here in Tucson to prove that we purchased our phones from Best Buy -an affiliate of AT&T.. that the store personnel would call the AT&T tech supports "back office" to verify where we bought our phones, you may think I was crazy, because I did go to an AT&T store to ask them to verify our purchase in that way. They said they never had to do that before but they put in a meager effort as they were busy, but that didn't work either to get our phones Unlocked by AT&T.

There is another Cell Phone Service Provider that still supports the Lumia 640 Microsoft phones but the phones need to be unlocked in order for us to get phone service from them. My only wish in this matter is to have our phones "unlocked" so we can have phone service again, as we need them for health and safety.