Violation of PRIMARY KEY constraint in Sql Server
<p>I have created a database with columns as first name lastname ,Id , date if arrival and  todays date. and all are data type of nchar(); I have ID as a primary key now in the web page i have entered vales and clicked on submit but is getting a error as </p>

<p>Violation of PRIMARY KEY constraint : Cannot insert duplicate key in object 'dbo.Accomdation'.
The statement has been terminated.</p>

<p>Code is given as </p>

<pre><code>    SqlConnection con = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=Accomdation;Integrated Security=True");
    con.Open();

    string f = TextBox1.Text;
    string g = TextBox5.Text;
    string d = DropDownList1.Text;
    string s = TextBox1.Text;
    string a = TextBox2.Text;
    string h = TextBox7.Text;
    string k = TextBox6.Text;
    string u = TextBox8.Text;
    string sql=("INSERT INTO Accomdation ([First Name], [LAst Name], Gender, [UHCL ID], [Date OF arrival], [FLight No], Email)VALUES        ('tya', 'tya', 'tya', 'tya', 'tya', 'tya', 'tya')");

    SqlCommand sw = new SqlCommand(sql,con);
</code></pre>
