If you're away from home it is still possible to access your Netduma router's interface.

In settings > miscellaneous tick "Access control panel from WAN(not recommend)." 

This means you will now be able to access the Netduma interface by typing your public IP address into your web browser. Now you could stop there, however this is a big security risk as anyone could then have access to it by typing in your IP address. 

Instead what we would recommend is that you Enable Password Protection on the miscellaneous settings page and enter a username and password you remember. 

Type "my ip" into Google to find your public IP address. Then copy and paste this into your browser's URL bar and press enter. You should be prompted to enter the username & password that you just set on the R1. Inputting this correctly should take you to the R1 interface.

If you cannot access it then you will need to ensure that the R1 is in the DMZ of your ISP hub/router. Click here if you are unsure on how to do this. 

Once you have successfully accessed the router interface you are able to change any setting that you would have been able to change at home.