Intel Realsense T265 camera not working on demo example

[dbgarasiya]

I am working on projects with two intel camera ( D435i and T265)

after installing robot_devkit when i play demo for both camera

D435i camera works but T265 camera not working , it gives error that device is not connected ( File name :T265_Error.txt )
which gives in details.
T265_Error.txt

my realsense-viewer command works for both camera ,

OS: Ubuntu 18.04.5 LTS (Bionic)