Galaxy Note 4 "unlocked" no mobile network

[AC Question]

We are tmobile customers and bought a supposedly unlocked phone from ebay that is the verizon model of the note 4. I am not getting a mobile network for some reason, and I don't think the phone has been unlocked. When asking the seller about what to do they sent me a link to a video that was about how you can use tmobile sims in verizon phones without unlocking, this lead me to believe that the phone has had nothing out of the factory done. That's fine if a tmobile sim works in a verizon phone on it's own, but I'm getting no mobile network. Can't make calls or texts.