i feel like i have a strange problem...

1 => i had a tp link tp link " tl-wr740n v6 " with original software ,
2 = > next i flashed it with openwrt the one which supports v6 , using firmware upgrade option.
     i enabled dropbear sshd server on it.
3= > then i flashed it back to the original software using TFTP server,

now i just had a nmap scan, results came shocking to me, it has still enabled sshd port open and listening, i diasbled root password authentication, and lost the  authentication keys.

question is  why do i have ssh server running? am i flashed it wrong, where did i go wrong ? how can it recover my router back to original state?

(Last edited by narutowindy on 10 May 2017, 10:06)