Flipkart — Refund of my laptop

I have purchased a Lenovo IdeaPad s340 serial no :- MP1R4FMV and it is in warranty due to repeatedly facing issue in laptop service declared it a DOA and they provide me DOA certificate and DOA sealed bag and i contact to Flipkart for replacement or refund and they accept it on 24th of August and tell me that product will be picked up 26 of August and refund will be generated in 1-2 days then a day before of picking someone call me from flipkart and tell due to technical issue the tracking Id had not generated yet so there will be delay and it will competed on or before 30th of August and same thing a day before a executive of flipkart call me tell me that your tracking id has not been generated because seller don't get acknowledgement of this return so we have to cancel request and again make it but they didn't do anything instead of that they cancel my request then next day I call to Flipkart and again i have to raise the return request they tell me it will be picked by 1 of September but till now no tracking has been generated they giving Tat regularly i have all proofs regarding this concern