Hi,
Update your code and see the result.
_localdt = new DataTable("GeneralInfo");
_localdt = PersonBLL.GetAddressesFromPerson(textBoxBranchName.Text);
dataGridViewAddresses.DataSource = _localdt.Tables["Addresses"];
And if it is not working then use below line to bind data.
dataGridViewAddresses.Grid.DataSource = localdt.Tables["Addresses"];