ASP.net bound fields connecting to SQL database using 3 joins - asp.net

Question

I have an ASP search style form that connects to a SQL database. I have figured out the code using SQL and I have been trying to add it to my ASP form. Everything I have tried just gives me the error "A field or property with the name 'A.FirstNameFirst' was not found on the selected data source".
Here is my front code:
<asp:GridView ID="GridView1" runat="server" CellPadding="4" Style="text-align: center" PageSize="2" Width="840px" ForeColor="#333333" EnableModelValidation="True">
<Columns>
<asp:BoundField DataField="A.FirstNameFirst" HeaderText="Full Name" HeaderStyle-BackColor="#99CCFF" />
<asp:BoundField DataField="B.ServiceLocation" HeaderText="Address" HeaderStyle-BackColor="#99CCFF" />
<asp:BoundField DataField="C.out_trans_dt" HeaderText="Bill Due Date" HeaderStyle-BackColor="#99CCFF" />
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:DatabaseConnectionString2 %>"></asp:SqlDataSource>
Here is my behind code:
Dim fnameSearchID, lnameSearchID, addressSearchID As TextBox
Dim searchItem As Boolean = False
Dim searchString As String
Protected Sub btnSearch_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSearch.Click
Try
searchString = "SELECT A.FirstNameFirst AS 'Name', B.ServiceLocation AS 'Location', MAX(C.out_trans_dt) AS 'Bill Paid' From [database].[dbo].[vw_Simple_customer] AS A JOIN [database].[dbo].[vw_location] AS B ON B.customer_id=A.customer_id JOIN [database].[dbo].[ub_financial_tran_detail] AS C ON C.location_id=B.location_id"
fnameSearchID = CType(DetailsView1.FindControl("fnameSearchID"), TextBox)
lnameSearchID = CType(DetailsView1.FindControl("lnameSearchID"), TextBox)
addressSearchID = CType(DetailsView1.FindControl("addressSearchID"), TextBox)
If String.IsNullOrEmpty(fnameSearchID.Text) = False Then
searchString += " WHERE A.FirstName LIKE '%" + fnameSearchID.Text + "%'"
searchItem = True
End If
If String.IsNullOrEmpty(lnameSearchID.Text) = False Then
If searchItem Then
searchString += " AND A.Surname LIKE '%" + lnameSearchID.Text + "%'"
Else
searchString += " WHERE A.Surname LIKE '%" + lnameSearchID.Text + "%'"
searchItem = True
End If
End If
If String.IsNullOrEmpty(addressSearchID.Text) = False Then
If searchItem Then
searchString += " AND B.ServiceLocation LIKE '%" + addressSearchID.Text + "%'"
Else
searchString += " WHERE B.ServiceLocation LIKE '%" + addressSearchID.Text + "%'"
searchItem = True
End If
End If
searchString += " GROUP BY ServiceLocation, FirstNameFirst"
Dim aSqlDataReader As SqlDataReader
Dim aSqlConnection As SqlConnection = New SqlConnection("Server=apphost007;Initial Catalog=database;User ID=user;Password=password")
Dim aSqlCommand As SqlCommand = New SqlCommand(searchString, aSqlConnection)
aSqlConnection.Open()
aSqlDataReader = aSqlCommand.ExecuteReader(CommandBehavior.CloseConnection)
'Fill gridview with search results
GridView1.DataSource = aSqlDataReader
GridView1.AutoGenerateColumns = False
GridView1.DataBind()
'set fields read only
DetailsView1.ChangeMode(DetailsViewMode.ReadOnly)
searchCriteria.Visible = False
searchResults.Visible = True
Catch ex As Exception
Response.Write("*** UNABLE TO SUBMIT SEARCH.*** " & ex.Message)
End Try
End Sub
Please let me know if you can see the error.