MI Power bank 10400mah — Mi power bank 10400mah faulty

I purchased this MI powerbank 10400 mAh and got it delivered yesterday. it worked till today morning, but stopped working since then.
I think its a faulty product.
The website owner is unreachable on phone and email. i think both the information is fake.
Please exchange it and provide a new one instead.
My shipping Address is 13 a ibrahim road, ekbalpore kolkata 700023.
name: Junaid Hossain.
contact number-[protected].