Issues on saving XML file after loading it on application startup

Question

I have a tracking program that saves a hidden XML file during a save or auto save in case the user accidentally closes the program and needs to load it back up. It is imported into a dataset and data table.

Here's the code for the WriteXML and ReadXML:

WriteXML:

 private void SaveloadFile()
    {
        string Timefor = Properties.Settings.Default.DateFormat;
        System.Data.DataTable dt = (System.Data.DataTable)dataGridView1.DataSource;
        string Filelocation = Properties.Settings.Default.SaveLocation.ToString() + "_" + System.DateTime.Today.ToString(Timefor) + ".xml";
        try
        {
            dt.WriteXml(Filelocation, XmlWriteMode.WriteSchema);
            FileInfo xm = new FileInfo(Filelocation);
            xm.Attributes = FileAttributes.Hidden;


        }
        catch(System.Exception err)
        {
            MessageBox.Show("Ah poop, Something went wrong\n" + err, "Oh poop", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
    }

ReadXML:

        public void ReadXML(string Filepath)
    {
        try
        {
            dt.ReadXml(Filepath);
            ds.Tables.Add(dt);

            dataGridView1.DataSource = ds.Tables[0];

        }
        catch (System.Exception err)
        {
            MessageBox.Show("Ah poop, Something went wrong\n" + err, "Oh poop", MessageBoxButtons.OK, MessageBoxIcon.Information);
            CreateDataBase();
        }
    }

And it seems to work. Although after opening the application and trying to save current work, I get this.

This only happens when I load the program and try to save.

I've looked into the code and I think I boiled it down to the readxml not letting go after reading. Though I have some suspicions that the writexml isn't working right ether.

I've looked around and I can't seem to find a solution to this bug.

If anyone can tell me what's wrong with the code that'll be great!