Paytm Mobile Solutions — fraudulent activity

I ordered iphone from paytm on 23rd july 2018 & paid approx rs. 25000 ; there was scheme of cashback rs.2500. I got message of delivery date extension to 28th instead of 24th july. Today when i queried about my product, i was told it is cancelled & i saw that they started refund of rs. 22000 which i will get by 9th august 2018 and balance amount rs.2500 they given in cashback. When i paid 25000 from my card, so i should have been given entire money back in my card. 2500 cashback i was entitled when i would had received the phone, but when phone is not delivered, why i am being forced to use services of paytm for my balance rs. 2500 in form of cashback.
I escalated this to paytm but executive refused for any support. They have no complaint email id where i can document my issue. This is fraudulent practice & i have experienced this issue in past also. On one hand they took money in advance, on other hand they cancelled the order without calling/informing me once. Worst of this, i am not paid full money & more than 10% of my amount credited in wallet instead of my credit card so that i may not uninstall this scrap app.
When i tried putting up this case online, i started getting call from "n" no. Of people who saying they are from paytm & then either ask me for credit card details for refund or give me farzi web of paytm (Paytmquery.in) which asks for credit card and paytm details. Please take appropriate action. I am giving you those fraud nos. Who started calling me on bahalf of paytm
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