Asp.net - A Field Or Property With The Name Was Not Found On The Selected Data Source

I have an Entity Data Model with two entities in it "Roles" and "Users". There is a navigation property from I have a EntityDataSource and a GridView. The EntityDataSource points to the Users entity and has an Include="Roles" parameter.I've added a BoundField in the GridView that points to RoleName, a property of the entity Roles. However, when I execute the code I get the above error.I have used very similar code successfully in another application. Any ideas why this isn't working?

Here is my EntityDataSource:

<asp:EntityDataSource ID="EntityDataSource1" runat="server"
ConnectionString="name=pbu_checklistEntities"
DefaultContainerName="pbu_checklistEntities" EnableDelete="True"
EnableFlattening="False" EnableUpdate="True" EntitySetName="Users" Include="Role">
</asp:EntityDataSource>

And here is the BoundField:

<asp:BoundField DataField="RoleName" HeaderText="Role" SortExpression="RoleName" />