What is going to happen with this bill?

Okay, so last year I made a mistake and I ordered this random stretch-marks-erasing cream. I told my mom and she called and we got it cancelled, but I still got the box with the product. Basically, it was one of those “try for 30 days for free”, and I wanted to try it. I didn’t think it would be a scam, but it was.

So now they’re calling me and they’re like “Oh, you have a balance of $138 and you have to pay it.” But I already canceled the account right after I made the order, and when I tried to send the box back it got sent back to my house.

I don’t really know what to do – I can’t afford to pay the money anyway.

Can they send repossession men on me or something? What can I do?