Complete Recovery Corporation for Equipment Return

I recently terminated my Xfinify service as I will be stay oversea for about half an year, and I did not see any items need to be returned on my Xfinity account after cancelling my service. But I just received an email from Complete Recovery Corporation asking to return a 4k Cable Converter Wifi that I have never used and is probably stored in my storage unit. Please let me know if there a way to resolve this?