Need an AT&T iPhone 6 factory unlocking service in HCMC

I think the iPhone became more difficult to unlock with software some time around the iPhone 5, 2012 or 2013.  I think it has something to do with randomizing the code that is applied to each phone.  A friend from the US, in good faith, bought my wife what was represented by the seller as a used unlocked 5C which turned out to be locked to T-Mobile.  We were unable to find anyone in HCMC who could do a software unlock.  We did find a SIM holder that goes in together with the SIM which worked for a while.  It was specific to Vinamobile and the first time we did an iOS system update, it stopped working and returned to a locked state.   

I'm sure there are genius hackers in HCMC but we never found them.   If you speak Vietnamese and you have plenty of time, maybe you could.   Be prepared for shops that say they can do it and have you leave the phone there only to come back in three days with no results.  My experience is that most Vietnamese repairmen never like to admit that they can't fix something even if they can't.

If you are still in the US and can afford it, go to AT&T, pay out your contract and have them unlock it.

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