c# Refresh Access Database

I am able to Save Data to a Access databse , now when i add new entry i try to refresh the database but the new entry dont show until i close the program and open it back up. I have 2 buttons one Update and the other Refresh. I am using Parameters. It would be better to use one meathod to do both (thats over my head at the moment) so i have 2 buttons. I dont get any errors when i try to Refresh so I dont know where to start.

Thanks

My Update code working fine.

private void btnUpdate_Clicked(object sender, RoutedEventArgs e)
{
using (var myCon = new OleDbConnection(ConfigurationManager.ConnectionStrings["Connection"].ToString()))
{
using (var myCmd = new OleDbCommand("insert into [Sheet1](Box1,Box2,Box3,Box4,Box5,Box6,Box7,Box8)Values(@nm1,@nm2,@nm3,@nm4,@nm5,@nm6,@nm7,@nm8)", myCon))
{
myCmd.Parameters.AddWithValue("@nm1", txt_Box1);
myCmd.Parameters.AddWithValue("@nm2", txt_Box2);
myCmd.Parameters.AddWithValue("@nm3", txt_Box3.Text);
myCmd.Parameters.AddWithValue("@nm4", txt_Box4.Text);
myCmd.Parameters.AddWithValue("@nm5", TXT_Box5.Text);
myCmd.Parameters.AddWithValue("@nm6", txt_Box6.Text);
myCmd.Parameters.AddWithValue("@nm7", txt_Box7.Text);
myCmd.Parameters.AddWithValue("@nm8", txt_Box8.Text);
try
{
myCon.Open();
int z = myCmd.ExecuteNonQuery();
if (z > 0)
{
MessageBox.Show("Data Inserted");
}
}
catch (Exception ex)
{
//Handle exception as needed
}
}
}
}

My Refresh is not refreshing the data base no errors givens.

private void btn_Refresh_Click(object sender, EventArgs e)
{
using (var myCon = new OleDbConnection(ConfigurationManager.ConnectionStrings["Connection"].ToString()))
{
using (var myCmd = new OleDbCommand("UPDATE Sheet1 SET Box1 =@nm1,Box2 = @nm2, Box3=@nm3, Box4 = @nm4, Box5 = @nm5,Box6 = @nm6, Box7 = @nm7 WHERE Box8 = @nm8", myCon))
{
myCmd.Parameters.AddWithValue("@nm1", txt_Box1.Text);
myCmd.Parameters.AddWithValue("@nm2", txt_Box2.Text);
myCmd.Parameters.AddWithValue("@nm3", txt_Box3.Text);
myCmd.Parameters.AddWithValue("@nm4", txt_Box4.Text);
myCmd.Parameters.AddWithValue("@nm5", TXT_Box5.Text);
myCmd.Parameters.AddWithValue("@nm6", txt_Box6.Text);
myCmd.Parameters.AddWithValue("@nm7", txt_Box7.Text);
myCmd.Parameters.AddWithValue("@nm8", txt_Box8.Text);
try
{
myCon.Open();
int z = myCmd.ExecuteNonQuery();
MessageBox.Show("Data Updated");
}
catch (Exception ex)
{
//Handle exception as needed
}
}
}
}