REFUND AMOUNT NOT RECEIVED

I have placed order on Flipkart (Order ID OD212270301845051000) on 9th May, 2018 for Mobile phone and cancelled that order on same day and ask for refund. But not received refund amount till date. I have done enquiry for the same many times through mail and phone call but they are saying that theier seller has done the payment against refund and they ask me to do enquiry in concern bank (SBI Bank, Kalwa Branch). I had registered a complaint in SBI on 16th May, 2018 regarding this. Now received mail from SBI saying that within 45 days your issue will be solved. I am not getting any proper reply from Flipkart and from Bank also.