It seems that there are some issues with the connectivity between the RUT and the VPN. The connection constantly restarts due to inactivity (ping-restart). Sometimes it restarts after a few minutes, but sometimes after less than a minute.
Maybe you have noticed internet connectivity issues with RUT956?
First of all, could you please try to delete your current RMS VPN Hub and re-create a new one?
Also, it seems that the device uses 07.02.7 firmware. Could you please update the firmware to the latest? RUT956 firmware is available here.