Scale Based symbology for size only in ArcGIS Online

[OliverSandoval_p]

Hello, 

Im truing to enable scale based symbology per this article Updated Arcade Code for Scaling Symbology (esri.com)

 However, i do not need attribute based symbology, every point's symboogy is just based off location so the same. This is my code. 

var vs = $view.scale
when(
    vs >=288895.277144, 3.5,
    vs >=9027.977411, 4.5,
    vs >=70.5310735, 6)

And I get this error

Any help would be greatly appreciated!