First, check whether the status of all configurations in TFS Administration Console--Reporting are configured well.
Then try to follow the steps below to manually process data warehouse and analysis services cube for Team Foundation Server:
- Log on to the application-tier server and open the Warehouse Control Web Service by entering the following URL in a supported web browser:
http://localhost:8080/tfs/TeamFoundation/Administration/v3.0/WarehouseControlService.asmx
- Choose ProcessWarehouse, click Invoke:

- Choose ProcessAnalysisDatabase. For processingType, type either Incremental or Full. Click Invoke:

To determine the processing status of the warehouse and Cube processing choose GetProcessingStatus to check the process status.
Detailed information check https://msdn.microsoft.com/library/ff400237%28v=vs.120%29.aspx?f=255&MSPPError=-2147217396