HDFC grievance cell giving nightmares

I am so fed up with HDFC grievance email responses. I applied for Tata neu rupay plus platinum CC which was offered LTF to me during the last month if applied before 31st. I applied before 31st, got the card approved on 6th Jan and delivered on 8th. I emailed them just to make sure it was LTF, but they took 14 days to respond back and to my surprise they said it's a paid card(they didn't mention the charges still, whether fyf or paid from 1st year itself).

All this while, I was constantly spammed with their whatsapp, sms, emails etc regarding activation of the new card. I responded back to that email with all the proofs, screenshots and everything that it should be LTF and they again have told me to wait for another 14 days. I got a call yesterday from HDFC and they asked about it when I rated them <5. When I said I have been missold the card, they asked if you have the LTF proof with you. My flabber was gasted at this point.

So, I want to know what should I do now? Should I let it deactivate by itself or use it for first year and close it before the annual charges apply(don't know if we can do that)? Please help.

Also, I want t carry this card only because it has a free dom lounge access but not at an associated annual fee.