Unfortunately this happens when using typed datasets that are not created by our report engine as the report wizard cannot find the table adapter only by its name in all cases. This is general problem as a whole and you can observe the same with Crystal, SSRS etc (if you created the dataset manually).
In short, you should initialize the TableAdapter and fill the data set in the report constructor manually.
You can also re-create the datasets through our report Report Wizard
if you have your database queries at your disposal and it would auto magically recognize the table adapter, initialize it and add the Fill() code in the report constructor for you.
the Telerik team