Arithmetic overflow error converting expression to data type int.

userid int
fname varchar(50)
lname varchar(50)
Email varchar(50)
Phone varchar(50)

ALTER procedure [dbo].[AddUser] @userid int,@fname varchar(50),@lname varchar(50),@Email varchar(50),@Phone varchar(50)
as
insert into UserInfo(Userid,Fname,Lname,Email,Phone) values(@userid,@fname,@lname,@Email,@Phone)

protected void Button1_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.AppSettings["con1"]);
        try
        {
            con.Open();
            SqlCommand cmd = new SqlCommand("AddUser",con);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddWithValue("@userid",Int32.Parse(TextBox1.Text.Trim()));
            cmd.Parameters.AddWithValue("@fname",TextBox2.Text) ;
            cmd.Parameters.AddWithValue("@lname",TextBox3.Text) ;
            cmd.Parameters.AddWithValue("@Email",TextBox4.Text);
            cmd.Parameters.AddWithValue("@Phone",TextBox5.Text);
            cmd.ExecuteNonQuery();
            Label1.Text = "Record Has Been Added Successfully!";
        }
        catch (Exception en)
        {
            Label1.Text = "Retry to add";
        }
    }