How to clear all points on WorldMap on a dashboard

Hi All,

I have created a map on NodeRed and am trying to create a button to clear all points on the map. However, the flow I built does not work. I have also tried the solutions suggested in the thread (Clear Worldmap with inject), however, as I am using a button (instead of inject), the solutions suggested cannot be applied easily in my case.

The flow I built for the button is as below.

Screenshot 2020-11-03 at 3.46.17 AM

And the function for the button is as below:

msg.payload.command.clear = "unknown";
return msg;

Could you please advise if I have made any mistakes, or what additional nodes/ functions need to be done to build a button on a dashboard to clear all points on the WorldMap? Thanks a lot.