Updating actual database rather than just the dataset

[Nat_xo]

Okay, so I was originally having problems even saving the data, but I can now get it to stay in the dataset, and when I switch to another page it stays there when I go back to it. Although when I close the form and reopen it, the changed data has not saved. I know that it is because I have only updated the dataset and not the database, so was hoping someone could give me pointers of how to approach it.
There are no error messages or anything coming up, as it works, just doesn't save into the actual database.

Cheers

This is what I have so far:

Private Sub btnsave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnsave.Click

        Dim cb As New OleDb.OleDbCommandBuilder(da)

        sql = "UPDATE tbl_CustomerDetails SET tbl_CustomerDetails.[Address Line 1] = """ + txtaddress1.Text + """ WHERE (((tbl_CustomerDetails.[Customer ID])= """ + lblidnumber.Text + """));"
       
        
        Me.Visible = False
        Homepage.Visible = True

End Sub

[debasisdas]

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