updateTargetBindings not working

Hi ,
I have object look like below
and I am trying to update the model using updateTargetBindings but its not working

just I am updating the geometry string like below
this.model.updateTargetBindings(this.model.nodeDataArray[2].states[0].geometryString, "M 28.3465 37.2047 M 23.4363 25.2461 A 10.5918 ");

anything wrong is here

Call Model.set (Model | GoJS API) instead.

this.model.set(this.model.nodeDataArray[2].states[0], "geometryString", "M 28.3465 37.2047 M 23.4363 25.2461 A 10.5918");