Problem while reverting to original firmware TpLink mr6400

I tried OpenWrt on my tp-link mr6400 v1.
When I found there is no easy way to view sms, configure data limit, configure openvpn etc (If I understand it is because it's an old OpenWRT version) I reverted to original TP-Link firmware.
I flashed the firmware by tftp method. It functioned.
I can access to tplink router admin by wifi connection on but when I try by eternet connection I fall on an endess loop trying to connect to OpenWrt admin. Like if a redirection script from OpenWRT stayed on the router on the ethernet port only. Any idea to correct this ?

During this endless loop I can read on the browser : "Luci - lua configuration interface", a link to :

Please try a different browser or clear your cache