Greetings All !!

I already have a Deco X60 AX5400 wifi 6 router as a main unit. I am able to update the firmware via Tplink Deco app from my mobile....

Recently I purchased a new similar model unit and connected it as secondary unit in another room. How can I upgrade the secondary Deco router ?? Via app I can only upgrade only the main unit and not the secondary.. 

Please help and guide.

Thanks in advance 

Best Regards 

Raj