Ambrane India — Poor product and service

I purchased a power bank from ambrane. (Line 20) .
I claimed its Warrenty because its a faulty one. They sent me the repaired one. But the repaired product they sent me again showed many faults after 2 to 3 months.
They have a warrenty of 6 months, but the product stopped working at 7 months.
They surely gave me a faulty product as a repaired one, or they are just causing nuisance and playing with customer's money. They are fraud.