I need solution for system.formatexception: 'input string was not in a correct format.'

private void btn_Add_Click(object sender, EventArgs e)
        {
            

                      if (radioButton_Male.Checked == true)
            {
                gender = "Male";
            }
               
            else
            {
                gender = "Female";
            }



                byte[] img;
                MemoryStream ms1;
                ms1 = new MemoryStream();

                pictureBox1.Image.Save(ms1, pictureBox1.Image.RawFormat);
                img = ms1.ToArray();

            RemindTextBox.Text = Convert.ToString(Convert.ToDouble(PatientCostTextBox.Text) - Convert.ToDouble(PayedTextBox.Text));

                Add_New_Patient.Add_Patient(

                 Convert.ToInt32(PatientIDTextBox.Text),
                 PatientTCTextBox.Text,
                 PatientNameTextBox.Text,
                 PatientAgeTextBox.Text,
                 gender,
                 PatientPhoneTextBox.Text,
                 comboBox_ShowState.SelectedIndex.ToString(),
                 dateTimeNOW.Value.Date.ToString(),
                 EmailTextBox.Text,
                 Convert.ToDouble(PatientCostTextBox.Text),
              Convert.ToDouble(PayedTextBox.Text),
                Convert.ToDouble(RemindTextBox.Text),
                 img,
                 NOTES_TextBox.Text
                 );
            
           
            

    


        }

public static class Add_New_Patient
 {

     public static void Add_Patient( int Patient_ID,string Patient_Identity, string Patient_Name, string Age, string Gender, string Phone, string Patient_State, string Patient_Date,
         string Patient_Email, double Cost, double Paid, double Remain,  byte[] Patient_img, string NOTES


         )
     {
         DXL.DXL ob = new DXL.DXL();
         ob.open();

         SqlParameter[] p = new SqlParameter[14];
         p[0] = new SqlParameter("@Patient_ID", SqlDbType.Int);
         p[0].Value = Patient_ID;

         p[1] = new SqlParameter("@Patient_Identity", SqlDbType.NVarChar,50);
         p[1].Value = Patient_Identity;

         p[2] = new SqlParameter("@Patient_Name", SqlDbType.NVarChar, 50);
         p[2].Value = Patient_Name;

         p[3] = new SqlParameter("@Age", SqlDbType.NVarChar, 50);
         p[3].Value = Age;


         p[4] = new SqlParameter("@Gender", SqlDbType.NVarChar, 50);
         p[4].Value = Gender;


         p[5] = new SqlParameter("@Phone", SqlDbType.NVarChar, 50);
         p[5].Value = Phone;

         p[6] = new SqlParameter("@Patient_State", SqlDbType.NVarChar, 50);
         p[6].Value = Patient_State;


         p[7] = new SqlParameter("@Patient_Date", SqlDbType.Date);
         p[7].Value =Patient_Date;

         p[8] = new SqlParameter("@Patient_Email", SqlDbType.NVarChar, 50);
         p[8].Value = Patient_Email;

         p[9] = new SqlParameter("@Cost", SqlDbType.Float);
         p[9].Value = Cost;

         p[10] = new SqlParameter("@Paid", SqlDbType.Float);
         p[10].Value = Paid;

         p[11] = new SqlParameter("@Remain", SqlDbType.Float);
         p[11].Value = Remain;


         p[12] = new SqlParameter("@Patient_img", SqlDbType.Image);
         p[12].Value = Patient_img;

         p[13] = new SqlParameter("@NOTES", SqlDbType.NVarChar, 50);
         p[13].Value = NOTES;


         ob.RUA("New_Patient", p);
         ob.close();


     }