Do you want to isolate each VLAN? If yes, any home router won't deal with this case. DHCP relay requires a router that supports multi-nets, or another switch that can work as DHCP Server. If it is...

I think no. I mean you should buy a new device. But if it still works fine after what you did, you can keep it.

@cmcouwenb No better ideas, and waiting for your port mirroring result.

No problem. Hope everything will be good after you install the omada gateway.

@Connectionloss I suggest you reset the EAP by pressing the reset hole. After resetting, do not configure anything, even the SSID and password, just connecting to the default unsecured SSID and check...

@Hoits When you connect the laptop to the LAN port of POE, can you see the LAN light on the CPE come on? Check if all physical connections are good. Try shorter cables.