having duplicate values when filtering a combobox based on selection from a list items

i have a list that have streetId and streetName filled when dgv1 is filled,in dgv2 i have a comboboxcolumn for streetName so i populate the street in it ,but i have a cabName cmbxcolumn i need to filter it based to the 1st column selection(streetName).i have a table camera:

camIp cabCode streetId camType camCode
  11.5    34       9    camtype1  PTZ
  11.7    34       9    camtype2   C
  12.1    19      10    camtype2   A
  12.2    19      10    camtype3   B
  12.3    19      10    camtype4   PTZ

and a table cabCode:

cabCode  cabName
 19      cabName1
 34      cabName2
 35      cabName3

Here what i've tried: I created a datatable for camera :

DataTable CamerastblUsage = new DataTable();
SqlCommand cmd5 = cnn.CreateCommand();
cmd5.CommandText = "SELECT cam.camIp,cam.cabCode,c.cabName,cam.streetId ,cam.camType,cam.camCode from camera cam , cab c where cam.cabCode = c.cabCode";

BindingSource unfilteredCamerasUsageBS = new BindingSource();
DataView undv2 = new DataView(CamerastblUsage);
unfilteredCamerasUsageBS.DataSource = undv2;
Column23.DisplayMember = "cabName";
Column23.ValueMember = "camIp";
Column23.DataSource = unfilteredCamerasUsageBS;

// this binding source is where I perform my filtered view
BindingSource filteredCamerasUsageBS = new BindingSource();
DataView dv6 = new DataView(CamerastblUsage);
filteredCamerasUsageBS.DataSource = dv6;

then i used the cellbeginedit event:

if (e.ColumnIndex == Column23.Index )
{
//filter cabCode combobox based on streetId selected in column index 0
DataGridViewComboBoxCell dgcb = (DataGridViewComboBoxCell)dataGridView3[e.ColumnIndex, e.RowIndex];

dgcb.DataSource = filteredCamerasUsageBS;
this.filteredCamerasUsageBS.Filter = "streetId = " +
Convert.ToString(this.dataGridView3[e.ColumnIndex - 1, e.RowIndex].Value.ToString());
}

but when selecting a streetName,example streetName1 that have Id 10 ,the filter gives in the cabName comboboxcolumn three same names of same cabcode 19:

cabName3
cabName3
cabName3

i need to filter it displaying only one name i think there is a mistake in the filtering,does anybody have an idea.