KanbanBoardWebPart-ppch.ts

 // Add this in the imports
import {
  IConfigurationService
} from "../../services";
// ....
// Add the following member to the KanbanBoardWebPart class
private config: IConfigurationService = null;
// ....
// Add the following method to the KanbanBoardWebPart class
public onPropertyPaneFieldChanged(propertyName: string, oldValue: string, newValue: string) {
    this.config.statusFieldInternalName = this.properties.statusFieldName;
    this.config.tasksListId = this.properties.tasksListId;
  }

// ...