Flipkart — Invoice not showing in my order section.

I purchased a boat airdopes161 last year in October. But now I am facing some charging related issue . As my product is under warranty I am trying to claim warranty for the same . But for that in I need to share my order invoice and its not showing anywhere in my order section in Flipkart. I have been trying to contact customer support Flipkart for 2-3 days but I am getting all executive busy response. I need an urgent assistance on my this issue so that I can get my order invoice to claim my product warranty.