rviz2 cannot show LaserScan messages in ROS2 dashing with gazebo

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Hi,

I am really frustrated that I have tried for almost one day before I put the question here. I really cannot figure out where is the problem.

I follow the turtlebot3 simulation to create my own gazebo robot, and It can be shown normally in gazebo and I can also tele-operate it. Please see the following picture from gazebo .

But when I open rviz2 and add LaserScan topic, the status shows OK, but there is no laser scan data shown. And I checked the topic list and topic echo it seems all OK. please see the following pictures.

Hope someone familiar with could help me out, thanks for advance.