Gantt diagram does not present the information

Question

I created a gantt diagram using a library from devextreme. I am trying to store the information in just 2 datasources, which differs from the example of devextreme. My problem is that the data is not shown in the diagram and I don't know where the problem is.

Someone can help me? Thank you

Library

DEMO

HTML

 <dx-gantt
    taskListWidth="500"
    scaleType="weeks"
    height="700"
    rootValue="-1">

    <dxo-tasks [dataSource]="Task"></dxo-tasks>
    <dxo-dependencies [dataSource]="Task"></dxo-dependencies>
    <dxo-resources [dataSource]="resources"></dxo-resources>
    <dxo-resource-assignments [dataSource]="Task"></dxo-resource-assignments>
    <dxi-column dataField="title" caption="Subject" [width]="300"></dxi-column>
    <dxi-column dataField="start" caption="Start Date" dataType="date"></dxi-column>
    <dxi-column dataField="end" caption="End Date" dataType="date"></dxi-column>
    <dxo-editing [enabled]="true"></dxo-editing>
</dx-gantt>