Can anyone tell me why this code wont update my SQL Server database?

I am trying to perform a simple update to a SQL Server database table and I can't figure out why this simple UPDATE command doesn't work. I am performing the same thing in another page for owner information and it works just fine. It seems that some of my code won't work even though the syntax is correct and there is no reason for it not to work.

I have hardcoded text for some of the fields and the UPDATE code below works but when I try to use the information that may be in the Textbox, the code won't do the UPDATE. Please help me figure out what is going on.

Thanks

Sub btnUpdate_Click_1(sender As Object, e As EventArgs)
 Dim UserCode as String
 Dim PropertyCode as String
 Dim UnitCode as String
 Dim address1 as String
 Dim address2 as String
 Dim address3 as String
 Dim city as String
 Dim zip_Code as String
 Dim description as String
 Dim price_Range as String
 Dim state as String
 Dim type_Property as String
 Dim property_Status as String
 if chkChangeState.Checked = True then
 state = ddl_State.SelectedItem.Value
 else
 state = lblState.Text
 end if
 if chkPropertyType.Checked = True then
 type_Property = ddlPropertyType.SelectedItem.Value
 else
 type_Property = lblPropertyType.Text
 end if
 if chkPropertyStatus.Checked = True then
 property_Status = ddlPropertyStatus.SelectedItem.Value
 else
 property_Status = lblPropertyStatus.Text
 end if
 txtPropertyCode.ReadOnly = False
 txtUnitCode.ReadOnly = False
 'address1 = txtAddress1.Text
 'address2 = txtAddress2.Text
 'address3 = txtAddress3.Text
 'city = txtCity.Text
 'zip_Code = txtZipCode.Text
 'description = txtDescription.Text
 'price_Range = txtPriceRange.Text
 UserCode = Server.HtmlEncode(Request.Cookies("UCodeCookie")("Code"))
 PropertyCode = txtPropertyCode.Text
 UnitCode = txtUnitCode.Text
Dim connectionString As String = "server='(local)'; trusted_connection=true; database='master'"
Dim dbConnection As System.Data.IDbConnection = New System.Data.SqlClient.SqlConnection(connectionString)
 Dim queryString As String = "UPDATE [Property_db] SET [Address1]=@.Address1, [Address2]=@.Address2, [Address3]=@.Address3, [City]=@.City, [State]=@.State, [Zip_Code]=@.Zip_Code, [Type_Property]=@.Type_Property, [Description]=@.Description, [Property_Status]=@.Property_Status, [Price_Range]=@.Price_Range WHERE ([Property_db].[Code] = @.Code) AND ([Property_db].[Prop_Code] = @.Prop_Code) AND ([Property_db].[Unit_Code] = @.Unit_Code)"
 Dim dbCommand As System.Data.IDbCommand = New System.Data.SqlClient.SqlCommand
 dbCommand.CommandText = queryString
 dbCommand.Connection = dbConnection
 Dim dbParam_code As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_code.ParameterName = "@.Code"
 dbParam_code.Value = UserCode
 dbParam_code.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_code)
 Dim dbParam_prop_Code As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_prop_Code.ParameterName = "@.Prop_Code"
 dbParam_prop_Code.Value = PropertyCode
 dbParam_prop_Code.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_prop_Code)
 Dim dbParam_unit_Code As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_unit_Code.ParameterName = "@.Unit_Code"
 dbParam_unit_Code.Value = UnitCode
 dbParam_unit_Code.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_unit_Code)
 Dim dbParam_address1 As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_address1.ParameterName = "@.Address1"
 dbParam_address1.Value = txtAddress1.Text
 dbParam_address1.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_address1)
 Dim dbParam_address2 As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_address2.ParameterName = "@.Address2"
 dbParam_address2.Value = txtAddress2.Text
 dbParam_address2.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_address2)
 Dim dbParam_address3 As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_address3.ParameterName = "@.Address3"
 dbParam_address3.Value = txtAddress3.Text
 dbParam_address3.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_address3)
 Dim dbParam_city As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_city.ParameterName = "@.City"
 dbParam_city.Value = txtCity.Text
 dbParam_city.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_city)
 Dim dbParam_state As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_state.ParameterName = "@.State"
 dbParam_state.Value = state
 dbParam_state.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_state)
 Dim dbParam_zip_Code As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_zip_Code.ParameterName = "@.Zip_Code"
 dbParam_zip_Code.Value = txtZipCode.Text
 dbParam_zip_Code.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_zip_Code)
 Dim dbParam_type_Property As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_type_Property.ParameterName = "@.Type_Property"
 dbParam_type_Property.Value = type_Property
 dbParam_type_Property.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_type_Property)
 Dim dbParam_description As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_description.ParameterName = "@.Description"
 dbParam_description.Value = txtDescription.Text
 dbParam_description.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_description)
 Dim dbParam_property_Status As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_property_Status.ParameterName = "@.Property_Status"
 dbParam_property_Status.Value = property_Status
 dbParam_property_Status.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_property_Status)
 Dim dbParam_price_Range As System.Data.IDataParameter = New System.Data.SqlClient.SqlParameter
 dbParam_price_Range.ParameterName = "@.Price_Range"
 dbParam_price_Range.Value = txtPriceRange.Text
 dbParam_price_Range.DbType = System.Data.DbType.String
 dbCommand.Parameters.Add(dbParam_price_Range)
 Dim rowsAffected As Integer = 0
 dbConnection.Open
 Try
 rowsAffected = dbCommand.ExecuteNonQuery
 Finally
 dbConnection.Close
 End Try
'if Not rowsAffected then
 Response.Redirect("./editproperty.aspx")
'end if
End Sub

Be sure to indicate parameter lengths for character-type data.

Terri