Flipkart — missing product serial number on invoice

1. I had placed an order for asus vivo book s series on 10 jun 20 my order id is order id was od[protected].

2. Product has been successfully delivered on 12 jun 20. However, on checking of invoice it has been observed that product serial number has not mentioned on the invoice for which i have lodged a complaint on 10 jul 20. The customer service has assured me that my issue is to be resolved by 13 jul 20 and thereafter 14 jul 20. However inspite of repeated requests to the customer service the issue has not been resolved so far.

2. Additionallly, i have registered for avail 2 years of extension warranty service @rs 99/- in asus. But, asus customer service has put my registration on hold due to the product serial number has not mentioned on the invoice and last date for submission correct bill is 16 july.