I created a database and a table in Microsoft SQL and I want to do some experiments on it with C#. I succesfully connected to my database and I can read the first row on the table too. But when I try to insert or delete some data, even though there are no errors, database is not affected.

Code seems to be correct. I think I need to change some properties about the database but I couldn’t solve it. Im 100% sure that there are no connection errors because read function is working. Maybe my database is closed to modify but I do not know how to solve it. Here is my code:

private void button1_Click(object sender, EventArgs e)
{
    //1- address of sql server and database
    string connection_string = "Data Source=LAPTOP-EC01498K\SQLEXPRESS;Initial Catalog=DENIZDB;Integrated Security=True;Encrypt=True;Trust Server Certificate=True";

    //2- create a new connection to that server
    SqlConnection con = new SqlConnection(connection_string);

    //3- open connection
    con.Open();

    if (IsConnectionAvailable(connection_string))
    {
        MessageBox.Show("Connection is formed!");
    }

    //4- prepare query
    string mail = textBox1.Text;
    string uname = textBox2.Text;
    string pword = textBox3.Text;
    string query = "INSERT INTO logging (email, userName, pword) VALUES ('[email protected]', 'tempName', 'password1425')";

    //5- execute query
    SqlCommand cmd = new SqlCommand(query, con);
    cmd.ExecuteNonQuery();

    //6- close connection
    con.Close();
    MessageBox.Show("Successfully signed!");
}