Problems Making A Userform Textbox Continue To Flash More Than 3 Times

I've run into a tad bit of a problem, I'm trying to make a userform textbox flash continuously if there is an error in it. What I keep ending up with is it flashing to green, then red, finally back to green (3 flashes total) and stays green until the error is corrected. I get the why, but I'm trying to make it go for a lot longer than those 3 seconds (or whatever I set the timer to). I've placed the code I've managed to put together so far below. As always, all help is appreciated.

BTW, I have tried using data validation, but that only appears to work if the userform is not used and the userform must be used in this instance.

Private Sub cboTime_AfterUpdate()

    If cboTime.Value = txtLTime.Value Then
      cboTime.SetFocus
        cboTime.BackColor = RGB(0, 255, 0)
        Application.Wait Now + TimeValue("00:00:01")
        cboTime.BackColor = RGB(255, 0, 0)
        Application.Wait Now + TimeValue("00:00:01")
        cboTime.BackColor = RGB(0, 255, 0)
        Application.Wait Now + TimeValue("00:00:01")
      ElseIf cboTime.Value <> txtLTime.Value Then cboTime.BackColor = RGB(255, 255, 255)
    End If
        
End Sub

If I could suggest a more common approach would be to display a helpful message and then don't allow the user to exit cboTime as long as it equals txtLTime. This would mimic how Data Validation works on a worksheet.

Private Sub cboTime_Exit(ByVal Cancel As MSForms.ReturnBoolean)
    If cboTime.Value = txtLTime.Value Then
        MsgBox "cboTime = txtTime" & vbLf & "Please make a different selection.", _
               vbExclamation, "Invalid Time Entry"
        Cancel = True
    End If
End Sub

Change the message text to suit.

I apologize for taking so long to get back this.

AlphaFrog, that actually works much better and is far more annoying, which is what I was trying to achieve. Thank you.

You're welcome. Glad it worked for you.