[Excel] Autohide of userform1 is not hiding the form

[Emeroogork]

Want to add a screen tip to a button in Excel VBA.

I hover over the button and the userform1 shows but the timer does not remove it 2 seconds later. I have to click on the X to remove it.

What might I be doing wrong?

Private Sub CommandButton1_MouseMove(ByVal Button As Integer, ByVal Shift As Integer, ByVal X As Single, ByVal Y As Single)
UserForm1.Show
End Sub

Private Sub Userform1_Activate()
Application.OnTime Now + _
TimeValue("00:00:12"), "Kill_Form"
End Sub

Sub Kill_Form()
UserForm1.Hide
End Sub