@Griggy Check this list - any would do the job for 2.4GHz and 5 GHz bands. If you want to extend the 6Ghz band as well only RE815XE would do.

@Jaggu1987 Rreset the RE to its factory defaults by pressing the rest button about 10 seconds and re-configure from scratch. If the issue persists contact your local support or if the RE is under...

@Eloik If you forgot the administrative password, you have to reset the RE to its factory defaults by pressing the rest button about 10 seconds and re-configure from scratch.

@ulululu Try changing the connected port LAN1 to another WR841n LAN port. If that doesn't work, use another ethernet cable and test again.

@Kerrya Connect a PC/laptop to your AX55 by a cable to one of its LAN ports. Here's how to find your router LAN IP address.

@sohouser This modem router is usually provided by ISP and there's no user guide available. Did you try to set Timeout to "0" and check what happens.