Punjab National Bank [PNB] — complain about my transaction

Address:

Dehradun, Uttarakhand, 249204

I purchased puma mens flexracer v2 pro shoes rs 1574 from amazon actually its 394.65 from amazon pay and remaining from my bank account 1179.35 on 09/01/2019 and done full payment by debit card but i returned my order on 11/01/2019 and now amazon is saying that refund has been send to bank on 12/01/2019 i get the amazon pay 394.65 but not remaining. So they say contact customer service and file charge dispute they had given me a no. Refund reference#75503729013026168124764
But customer service is saying they can file nothing like charge dispute and can only check if money came to your account or not.
Same behaviour by branch also.
Don't know what to do