How to fix invalid object name ?

See more:

C#

SQL

hi this is my code :

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;





namespace naft
{
    public partial class M : Form
    {

        
        SqlCommand cmd;
        SqlConnection con;
        SqlDataAdapter da;


        public M()
        {
            InitializeComponent();
        }
        private void BtnSave_Click(object sender, EventArgs e)
        {
            con = new SqlConnection(@"Data Source=SHADOW\AL;Initial Catalog=Filelib;Integrated Security=True");
            con.Open();
            cmd = new SqlCommand("INSERT INTO M (M_Name, M_Code) VALUES (@M_Name, @M_Code)", con);
            cmd.Parameters.Add("@M_Name", TxtM_Name.Text);
            cmd.Parameters.Add("@M_Code", TxtM_Code.Text);
            cmd.ExecuteNonQuery();
        }

when i want to insert name and code it show me this error : invalid object name Naft ( after i change it to "m" it says invalid object name "m" )

"naft" is my sql database and the table that i want to insert data is "M" how to fix it ?

What I have tried:

i searched a lot but i can't fix it.