Airtel Payment Bank — Cashback scam by airtel

It’s airtel bank regular practice of scamming customers by showing cashback offers but not providing it. It’s now the third time with me. Last two times I ignored but this time I thought of catching them. According to their offer I was suppose to get 50 cashback for my landline payment of 801/- but Didn’t get it.
So wrote them a mail, surprisingly first they told that they have no such offer, luckily I had screenshot so I gave it to them, after that they gave me only 30/-

Now again I have wrote almost 15-20 mails to them regarding incomplete cashback but they are shamelessly replying me that 30/- has been credited to my account. I have been repeatedly asking them about remaining 20/- but they are intentionally ignoring the question and replying me same 30/- mail again and again.

Re: Complaint regarding cashback [protected] [CASE:8444343] [CASE:8461425] [CASE:8493381] [CASE:8537841] [CASE:8560143] [CASE:8585541] [CASE:8604267]

These are my case IDs, also attaching screenshot of offer and my transaction ids.

I wish most strictest action should be taken against these companies.