Traffic Analyzer - Statistic, no data

Hi there.
I am using Asus RT-AC68U with Firmware:378.55
Under Traffic Analyzer / Traffic Analyzer - Statistic i dont see any information. I have turned on the feature and wait hours....i see no information on the graphics! what am i doing wrong? Could you please help me with these!? The client list displays no clients. It seems like there is something missing!
Any help would be really apreciated!