I got a Sprint iPhone 6 from Best Buy pre-owned, and contacted Sprint today. The only info they needed was the MEID, and after a lengthy wait told me they it was unlocked. They didn't need the previous owners account info or anything. When I put my T-Mobile SIM in to activate the phone, I still get the SIM Not Valid message. I contacted chat, who confirmed that it shows as unlocked. They told me it could take up to 48 hours to go through. Has anyone else and to wait, or is it usually instant? Thanks.