I got an iphone 5 but can't use it?

I bought an At&T iphone 5 on ebay for $400 and wanted to use it with Straight Talk, a $45 a month carrier. But apparently I can only use phones that I buy from Straight Talk. Is there anything I can do to still use my phone? Like unlock it?

Well you need to figure out what carrier it is currently locked to and get it unlocked and then see if you can get a SIM card from that company.

Odds are if it was locked to a carrier the phone is in poor standing meaning now you have to pay off what they owe the carrier to have them take care of the phone.

This is why you get the serial number and IMEI number beforehand so you can talk to the carrier so you know what status the phone is in and to talk to Apple and see what's going on with the phone in terms of warranty

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