Flipkart — Regarding non payment of flipkart pay later

Few months back I ordered a redtape shoes and a book using the flipkart pay later service but when the shoes delivered to me It was defected so i try to return these shoes, but when i trying to return these shoes the flipkart blocked my account. So i am neither be able to return this order not be able to do payment of my flipkart pay later. I tried many times to communicate the flipkart customer services but all in vain. Now when i checked my cibil score it shows pending payment in my credit score and all my loans are effected by it . I am no able to take any loan because of this. Kindly please solve this problem. thanks.