Populate a data field from a dropdown

I have a page for updating 'tableA'. I have a dropdown on the page for values from 'tableB' that has columns id and name. Name is displayed, but I want to store the id value in 'tableA'
I have the dropdown correctly populating the dropdown, but I cant seem to get the id from tableB to store into tableA from the selected item.
I have the TextProperty set to 'name' and the ValueProperty set to id.
I do not see anywhere in the designer.cs where these values are manipulated.

Do you have any suggestions?

This seems to be the correct configuration. Now the Value property of the DropDown will be the id of the selected item from tableB. What is the Value property of this DropDown set to? It should be set to the foreign key column of tableA.

Radzen automatically generates such dropdowns and correctly configures them when there is a foreign key constraint between tableA and tableB.