@Jorico Either change the cable between your main router and C6 with another one (Cat5E/6) or use another LAN port on your main router to connect to C6. It's best to use factory made ethernet cables,...

@VC7 No, you don't need two network adapters for running VM Hub3 in router mode - here you can see how to switch from modem to router mode. After switching VM Hub3 to router mode, re-configure the C7...

@Nokuroku You have three options: 1. Return AX1800 and buy another WDS capable router like Archer C7 or Archer C2300. Keep in mind that it's a 450 mbps (on 2.4GHz) router, and the theoretic maximum...

@Kaivu I meant after resetting the router to factory defaults, connect a PC with an ethernet cable to the router LAN port and configure its settings. This video may help you configuring the router.

@Stenness Is the iPad Pro the only device that has a problem connecting to 5 GHz ? Have you updated its iPadOS version to the latest ? Are you using any special feature like Access Control, IP & MAC...

@Kaivu . On the bottom sticker you should have the default wi-fi passwords which you should use after resetting to factory defaults. Otherwise connect to the router by ethernet cable (LAN port) and...