Myntra.com — regarding refund of rs. 1996 nike joggers

I have returned nike joggers bought from myntra on 3rd february 2020. As of now it's more than one month passed but i have not received the refund amount yet. Every time when i contacted myntra they continuously saying that from our end the refund is successfully transferred but i haven't received the amount. They are saying that you should contact the sbi bank since i have made payment through google pay upi (Sbi). I have contacted the bank but they are not replying to my mail and on calling they are saying that myntra is a third party application and we can't help you in this matter. I have tried my best to tell them i have not received the amount. But now i am tired and frustrated calling them because i am not getting any right response from them. So kindly help me out in getting my refund.