I understand that you received the Samsung A31 from your uncle, but it seems that you need the network unlock code to use it with a different carrier. In this case, you may need to contact the original carrier that the phone is locked to in order...
May nadiscover akong site which provides unlock code di ko pa talaga natetest dahil wala akong cp na naka network lock pero nacheck ko trustpilot ratings nila so far goods naman
If may device kayo na naka network lang try natin openline:
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