Unhandled Exception

Question

please I'm trying to insert values from a textbox into the database. but I'm having this error when debugging
" No mapping exists from object type System.Windows.Forms.TextBox to a managed provider native type." please help this is my code for the connection
 private void SaveBtn1_Click(object sender, EventArgs e)
        {
            try
            {
            string connectionString = @"Data Source=JEREMIAH-HP\SQLEXPRESS;Initial Catalog=CgpaCalculator;Integrated Security=True";
            SqlConnection sqlCon = new SqlConnection(connectionString);
            sqlCon.Open();

             using (SqlConnection connection = new SqlConnection(connectionString))
             using (SqlCommand command = connection.CreateCommand())
        {
            command.CommandText = "INSERT INTO StudInfo(Matric_ID, First_Name, Last_Name, Dept,Level,Cgpa,Entry mode) VALUES (@Matric_ID, @ First_Name, @ Last_Name, @Dept, @Level, @Cgpa, @Entry mode)";

            command.Parameters.AddWithValue("@ Matric_ID",matricNo);
            command.Parameters.AddWithValue("@First_Name",frstName);
            command.Parameters.AddWithValue("@Last_Name", lstName);
            command.Parameters.AddWithValue("@Dept",department );
            command.Parameters.AddWithValue("@Level",Level );
            command.Parameters.AddWithValue("@Cgpa",cgpa);
            command.Parameters.AddWithValue("@Entry mode",mdeofentry);

            connection.Open();
            command.ExecuteNonQuery();
        }
    }
    catch (SqlException ex)
    {
      MessageBox.Show("There is an Error in saving file" + ex);
    }
        }