No binding data in bound table in WPF

[Bear89]

Not sure if anyone can help me with this one. I have 1 parent and 3 child tables in my WPF design, with the 3 child tables bound to the parent using drag and drop from the datasource. However, one of the tables displays no binding data. When I check its Bindingdata resources they are all present, and if I change the resource to another bound table I get all that table's appropriate bound data. I can find the names table in XAML but the table doesnt have all the descriptors that the other children have.

Not sure how to get these data back. I have tried deleting and dragging and drop, but the same behaviour recurs.

Any thoughts?