Trying to "unlock" Iphone SE purchased online

[Ann1917]

I purchased an SE from someone selling online. She did provide the IMEI # prior to my purchasing and it showed it was not blacklisted. She set to factory settings. But when I went to Sprint to have the phone set-up. I was told that it was still listed with another owner under contract and a particular phone number that was originally set-up. I bought the phone for my son. What steps can I take to be able to use it for our personal use? I have another iphone 5 that is currently set-up with Sprint. Can I take the SIM card out of that phone to use in this SE phone? Any help would be appreciated.

 

[rgd1101]

If it still under contact it will not be unlock. The owner have to pay it off first, contact the seller.