Ion Exchange India — Unable to get refund of the Purchase order they failed to deliver

Address: Alipore new market, Kolkata

I am an unhappy dealer of Ion Exchange India's ZeroB products based in Kolkata.
First of all many of my clients and consumers are so unhappy with the products they purchased and also their services are third class. Moreover, their behaviour towards the dealers and clients are very bad

Secondly, one of my clients ordered some products from me for which I gave the purchase order to ZeroB Co. which they failed to deliver as a result I lost my client and the trust of my client. After they failed to deliver the PO, I asked for the refund and they agreed but they are taking too much time which is getting frustrated. Everytime I call them they give me a date and that date gets passed and they would give me new date and then again same incident happens. 2 months have passed and still no refund I got. Now they are not responding to my mails or my calls.

Please help me sue this company so that many unhappy dealers and consumers doesn't get frustrated and irritated by their unacceptable behaviour.