State Bank of India — Charge dispute against SBI

My name is Smita Sahoo. I had ordered " Lovable Women Girls Cotton Non Padded Non Wired Full Coverage Bra in Black Color-X-Bra - Black" of Rs 355.00 from Amazon.in on 23rd October 2020. On 28th October 2020, I returned the product due to some personal reasons. On 29th October 2020, Amazon initiated the refund to my card which was expected to be credited within 3rd November 2020. But I still have not received the refund. Amazon has sent this refund reference number- 05170 and asked me to file charge dispute. But the SBI helpline number is not working and neither the associates are helping with this matter. Kindly respond to this complaint since it is very urgent. My card number is [protected].
Thank you for your help.