SQL C# Datagridview removing mutiple rows at the same time

i am trying to select multiple rows and deleting all of which

private void btnDelete_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(txtAMDID.Text))
            {
                MessageBox.Show("برجاء تحديد عنصر للحذف");
                return;
            }
            else
            {



                try
                {
                    foreach (DataGridViewRow row in dgvActiveMaterials.SelectedRows)

                        dgvActiveMaterials.Rows.Remove(row);
                    
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);
                }



                int I = CLASS_ACTIVEMATERIAL.SP_ACTIVEMATERIALDELETE(int.Parse(txtAMDID.Text));
                MessageBox.Show("تم حذف المادة بنجاح");
                btnSelectALL_Click(null, null);
                txtAMDID.Text = txtAMNAME.Text = txtAMDescription.Text = txtSearch.Text = string.Empty;
            }
        }

and here is my delete method

DataAccessLayer.Open();
            int I = DataAccessLayer.ExecuteNonQuery("SP_ACTIVEMATERIALDELETE", CommandType.StoredProcedure,
                DataAccessLayer.CreateParameter("@ACID", SqlDbType.Int, AMID));
            DataAccessLayer.Close();
            return I;

and here is my stored proc for deletion

PROCEDURE [dbo].[SP_ACTIVEMATERIALDELETE]

@ACID INT 

AS
DELETE FROM tblActiveMaterial WHERE Am_ID=@ACID

RETURN