Your picture cuts off text that appears to be describing a problem that exists in the source data. Without the data or the complete message we can't tell what the actual solution would be.
The message indicates that something in your data is not working with the selection you make. My first guess, based on the box that says "Select a data source" with an X means you haven't selected the data.
My second guess would be that none of your data sets have the correct types of values for whatever you are attempting.