At first I can acces the RUT240 from internet perfectly, port forwarding works OK and I can access to devices in my home network. But sometimes access from internet is lost, after few minutes or hours. Acces to internet still works well. Public IP remains the same all the time.
But then I login via WebUI to RUT240 from home network to 192.168.1.254 and select >Network >Mobile -setting page, I can acces the RUT240 from internet again.