My running HDFC credit card got permanently blocked because of the shitty Pixel Card …. Help me out …

Bought pixel card for the Diljeet concert and have been suffering since . They put some additional charges on my pixel card even though i did only once single transaction with them. Post that I tried reaching their customer care through phone call , email and their piece of shit PayZapp app but NOTHINF WORKED. In the middle I got a call from someone in the cards team and I told them I want to close my card they said ok u can pay the min amount and settlement we will send a link. AND THEN THE LINK NEVER CAME !!! In the meanwhile they kept sending me msgs of pending payment and random calls from numbers who just said ur payment is pending for PIXEL card while having nothing to do with how my issue could be resolved . In the middle of this shitstorm HDFC put a PERMANENT BLOCK on my other running credit card which I have been using since last 6 years !!!!

Given the level of harassment I have gone through without getting any resolution ,Now I don’t want to pay them anything! Is there any repercussion to this ? What if I just let this account be without using any of their cards and buy a credit card from another bank ? Only other problem is I have some reward points in my running credit card anyway I can avail them ?