HDFC Bank — Refund amount not reflecting

Hello HDFC team,

I have been trying to reach you via your customer care number, seems you're not taking any calls due to Corona outbreak.

I have returned few of the ordered products from Amazon, Marks & Spencers and Swiggy. The amount got refunded from their end but has still not refelected in my account. They have provided me with various reference number as well but it is impossible to contact your bank.
It's been aorund 5-6 months since an amount of Rs. 4000/- (approx) has not been credited in my account. I'm really worried now beacuse this has become a consistent practice from different vendors where they are asking me to contact my bank.
Request you to please contact me at the earliest.

Regards,
Neha Singh