ODBC Data Source unable to read names

Hi All, 

I am working with our HR staff to automate the creation of our organizational charts. We store our "Reports To" information in a Smartsheets database. The Visio organizational chart wizard gives you the option to upload data via n ODBC-compliant data source. I then select my data source and choose the correct table. But when I do, the following error appears: 

"Unable to read names from ODBC data source.". 

Does anyone know why this is happening or how it can be fixed? 

Thanks!