Compete Recovery Corporation

I have received multiple emails from Complete Recovery Corporation stating "We would like to help you with your Xfinity equipment listed below that must be returned. Equipment: X1 HD Cable Box Serial Number: CSXXXX" |

This WAS a legitimate cable box that I had that I stopped using months before I ended my service completely, but I sent that back via the UPS store months ago. All other equipment was returned directly to Xfinity when I ended my service. Can you check into this and ensure I am not going to be charged for this, and I get my refund balance returned ASAP?