Amazon — doesn't give me refund reference number but telling me i've been credited

Address:	621216
Website:	amazon.in

I purchased a product named resist uv protection golden metal frame with blue gradient aviator sunglasses for men and women sold by: j t ventures
From amazon, and i've returned it, but didn't receive the payment, i contacted customer care service on january 4th 2018 about my refund, they said they've initiated and i should have got it on january 1st 2018 and i asked the refund reference number they said i should wait for 24 to 48 hours, but its more than 3 days i didn't receive the refund reference number. So today 7th january 2018 i contacted amazon again and they are telling me they don't have it??? And i should wait again to get the number. This is very annoying when i've returned the product safely but they are not doing their part (Refunding). And this is not the first time i'm facing this issue