Multiple colour shades coming when connecting 1280x800 resolution display

I am just trying to integrate a HDMI display having 1280 x 800 resolution : display info with Google coral developer board : link.

After changing the resolution (1280 x 800) in the file : weston.ini. while connecting the display to the board i can get the display modes as shown below... (but not showing my current resolution 1280x800)

mendel@mocha-ibis:~$ cat /sys/class/drm/card0-HDMI-A-1/modes
3840x2160
1920x1080
1280x720
720x480

The display started showing multiple colour shades which is not expected one... Please guide me / suggest me, Is any thing there to be configured to fix this issue..

Edited Dec 30, 2020 by Bhanuchander Udhayakumar

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