Moglix — Defective product

I bought AC Stabilizer in Moglix. After installation it worked only for once, second time it is not giving power supply to AC. At first we thought it is AC fault. But technician said it is stabilizer fault. We booked complaint in Moglix, but they told to contact company customer service. We took product to service centre. They simply said that, this is not a new piece, we don't give free service to this.

Why did moglix cheated us with second hand/refurbished products. Pls give us proper solution for this issue.