@HomeAdmin Yes, I can ping and SSH but unable to access the controller. Either directly from a pc and when i go to the app or https://omada.tplinkcloud.com/#controller it does not show the controller...

@tlr6052021 I was able to get the controller on Raspberry Pi working . Everything works fine for abotu 3 or 4 days and then I cannot reach the controller. I reboot the Pi and then everything works...