i have bought samsung galaxy S9+ from a third party seller. How do unlock it ? T mobile is asking me for account number, but, i have never bought a sim card, neither i do have any account number to give them.
To unlock a Tmobile phone you need to have a Tmobile USA account and
meet the requirements in the link below.
So basically Tmobile won't unlock it for you.
Unlock your mobile wireless device
Retrieving data ...
Manage your T-Mobile account
Use the T-Mobile App or your My T-Mobile account
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