I have list of services (Object) in my grid. I've added a record (Services Object) on different page. Then, refresh the grid when I came to Grid page. I have got the error below.

An error occurred while refreshing the data from field 'Services.unitset_id' to property 'SelectedValue' on control 'editUnitSet.'

When I open the page from menu. I have seen the added record.

Well, there seems to be quite a bit going on, but the last error seems to be the easiest to dianose.  It is a cast exception so that value that is being passing into the Set of the unitset_id field is not a type that can be converted into the type it is expecting.  For example, this may be a integer field and character data is being passed into the Set of the property.