@AnujBangera
Hi, May I know your A6 region version? Is it EU or US or other custom versions?
we don't suggest customers upgrade the device firmware across regions and it will be against the warranty, you may kindly wait for the new firmware for your device on the local TP-Link official website of the purchase location for your TP-Link device. A wrong firmware upgrade may damage your router or cause the router to not function properly.
If your A6 is EU version, please check and ensure you've unzipped the downloaded file from the official website before upload it into the router:
How to Upgrade the Firmware on the TP-Link Wi-Fi Routers
Good days.