There was a poor soul that bought an unlocked phone and they did a factory reset. BLAMMO it was locked again to a carrier. Samsung would not unlock it. This poor soul was very upset but won't accept that Samsung has agreements with the carriers about unlocking (Samsung does not unlock phones, the carriers do that.)
To add more trouble to their predicament the unlock seems to be to slip in the old carrier's SIM and perform some button presses while the phone is connected to the old carrier's network. Which they can't because they are in another country.
Seems to be a recurring story and why some deals are just too much trouble.
Samsung has just returned my "new-to-me" Galaxy S7 Edge *without* taking 5 minutes to reload the Boot Code, without the dreaded FRS boot loop demanding the original owner's Google Credentials. (At one time, it was probably a corporate phone.) Samsung does not (and dares not) dispute the validity of my purchase. But, they refuse to touch it - maybe because the phone is about 8 months out of warranty. Would you buy a car, if you knew that PAID-FOR manufacturer service would be discontinued on the minute it went out of warranty?
First, they closed two of my "support cases" without reply to my email or my other phone (which is, unfortunately, another Samsung). Then, they created a third "support case" and sent a shipping label. They declared the repair for their nasty "LOCK DEVICE LOCK PRIVACY LOCK" to be $70.31. I happily paid it.
But then, they declared that they're shipping the phone back un-repaired. All that I had done was apply a touch-wiz update to enable correct (and settable) screen pressure for touch and swipe actions. I am left with a $200 BOAT-ANCHOR, which they could have fixed in less than 5 minutes. They chose to give me the shaft.
(My Samsung S7-Edge "boat anchor" is not waterproof, and doesn't weigh enough to actually anchor a boat.) I therefore warn anyone who contemplates buying a new Samsung S9 (or S10) phone- they release their phones to the market before the software is fully functional, and any used buyer will be *killed* if they try to apply a software update. You should probably assume that you are trapped in a Samsung treadmill, with each $900 phone "supported" only for it's warranty period, and un-sellable to anyone else.

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