Apple

So I brought an Apple Watch SE from the pawnshop for $100. Everything works fine, but I’m trying to add a line to my phone so it all can be connected together number and all. And T mobile telling me they can’t do it/add a line until I pay off my payment arrangement. Which I cannot do until Friday and the lady told me she can check the status of the watch to see if it’s not paid off or still under someone else account since I brought it at a pawnshop. But I have a certain amount of time to return it if anything wrong. So my question is how can I check the status myself ?