@Andrewspan Thanks everyone, the problem was with the internet provider, I disconnected the WAN cable and restored access to the controller.

@Clive_A Hi Clive_A. I replied to Vibis in Russian because his post was written in Russian.

I have the same problem with some equipment after replacing ER7206 router with ER707-M2.

Hello. This morning, three controllers lost access via the Cloud. It shows the status as online, but when I try to log in, the message "Connection failed. Please refresh your browser and try again"...

@Vibis Виртуальные сети делаются на Микротике, а на портах свича назначаете нетагированные и тагированные VLAN