Call Activity Assignee

I have a flow ,and contains Call Activity. I want to assignee for one task. I hope all the assignee will to be change when match same role type(role type field in the variables map).
Now, i use TaskService.setAssignee(String taskId, String userId) to assignee task without call activity.
So , how can i change call activity user task assignee by the code.

The first picture is main work flow.
image

The second picture is will be use for main work flow.
image

Which tool are you using to model this process?

Use Web Tool to model. In addition, I also use the Camunda Modeler tool