Nvblox seeing false obstacles that get cleared after sometime but causes Nav2 to fail due to obstacles

I am using Nvblox with lidar and Nav2 for Navigation. The output of Nvblox goes into Nav2. I see that Nvblox detectes fake obstacles on robots path which causes Nav2 to fail as it fails to find any valid trajectory. However there are no obstacles in front of the robot in Issac sim. If the robot is stationary those obstacles clear out after sometime.

Can anyone suggest what can be done and which would be the right parameters to tune to get around this issue?