1 of 1 people found this helpful
You can't only the seller can.
If the phone is blocked it can't be used on any network because of loss,theft or non payment.
If it's sim locked it can be used with Tmobile but not any other network.
1: You must be a current Tmobile customer. If not, don't proceed to the rest of requirements.
2: Meet the usage requirements. 40 days of use on post paid or 1 year of usage or $100 in refills for prepaid.
3: The account associated to the original owner of phone must be in good standing.
There's other requirements but those are the main three.