can anyone help me on this textbox issue:

Private Sub IBAN1_AfterUpdate()

IBAN1.Text = Format(IBAN1.Value, "#### #### #### #### #### ####
#### #### ##")

End Sub


when the user enters numbers, the textbox is change the input.

example 1255 2222 3333 3666 5555 6666 99999 88888 88

1255 2222 3333 3666 0000 0000 0000 0000 00

any ideas