Nighthawk R6900P - "didn’t send any data" when trying to edit device

I am attempting to rename some devices.  I go to "Attached Devices" and check the box on the row for "Fire TV Stick".  As it happens, that's not actually a Fire TV Stick, it's an Echo Dot.  So, I check the box and click on "Edit" and put "EchoDot" as the model name, change the device type to "Smart Speaker", and click "Apply".  The frame goes grey with frowny paper icon and the message, "192.168.1.1 didn’t send any data".

How can I fix this?  Thank you.