@Akarv Follow this guide for troubleshooting your issue. If that still doesn't work you can use the MR200 remote management: Go to Advanced > System Tools > Administration page. Locate the Remote...

@Giff As far as I know you have to setup the correct PPPoE settings when in 'wireless router mode': Provided you use FTTP and do not have BT Digital Voice. You will need to enter the correct login...

@Giff If you want to use VR2800's LAN4 port as WAN port you have to switch its 'Operation Mode' to 'Wireless Router Mode':

@Tonylr You can use any RE to expand further your wireless coverage, but go through this FAQ - Part 3 - Q3.6/A to see how you can do that more efficiently.

@Piie OneMesh doesn't support an ethernet backhaul - OneMesh FAQ - Q5/A5. OneMesh is not supported by Omada EAPs either. If you want, you can use an ethernet cable to connect the RE505X to your AX20...

@Reckless Use this video guide for more detailed steps for setting up the extender.