**FYI am currently living in Japan, but with my beginner Japanese language ability, am unable to communicate well about this complicated situation, thus I came here to ask for assistance**

**THIS IS NOT FOR ARCHER AX55. It is for Archer AX5400. I could not find it in the 'Model' dropdown menu**

-- Setting up my WiFi --

I recently received my modem (recommended by Docomo) and then my router (recommended by Docomo, also, giving me the option to go with a company called GMO) to set up my WiFi at the house.

I followed the directions, used Google Translate to take pictures and translate everything. I set it up by myself... and afterwards, my WiFi was working perfectly.

-- What happened -- 

Yesterday morning (JST),

I was doing my usual check, I tapped my Tether app on my phone and I saw a notification within the app. It was about a firmware update. Naturally, I thought that I could just update the firmware and make things smoother, but I was mistaken.

After updating the firmware (it took about 3 minutes and 30 seconds), an orange LED turned on my AX5400 v1.0 router, near the planet icon (for the internet) and my WiFi was on but it wasn't working properly. That LED was white before the firmware update (my router used to connect perfectly to the internet after I set it up). For example, the connection timed out and therefore unable to open a webpage. Strangely, it worked however, for a short while (a few hours) on other devices than my smartphone (iPad and wife's phone).

It was 100% my fault to update the firmware manually on the Tether app and in retrospect, I should have simply let the device update itself with the auto-update function already enabled. 

What I've already tried:

- Rebooting the router

- Rebooting the modem

- Rebooting both

- Rebooting to factory default and trying again 

Nothing I'm doing seems to fix the problem and I might have made things worse - I'm still not able to get my router connected to the internet.

I would like to understand exactly what went wrong and what I can do to fix it/find a solution.

In the meantime, it appears that I should contact my ISP, called GMO. First, I think I need to contact TP-Link, however.

I am grateful in advance, for your assistance and/or advice of any kind.

Thank you