exit a form getting "Runtime Error 91: Object variable or with block variable not set"

I have a bit of code I have used for years and recently under a slightly different application we have a bug. in the following code, if cell B4 = "z, row" we need to display the message box and close the form. however, regardless us what I try to Exit Sub I get "Runtime Error 91: Object variable or with block variable not set"

Private Sub UserForm_Initialize()
Dim lastrow As Integer
Dim frmTop As Integer
Dim cbnOfSt As Integer
Dim varAnswer As String

'bail out code
 If Range("B4") = "z, row" Then
    varAnswer = MsgBox("This worksheet has only one employee. A new employee must be added before the current employee can be removed", _
    vbOK, "Minimum Employee Warning")
    
        If varAnswer = vbOK Then
                Unload frmRemEmpl, some results with "unload me" 
                Exit Sub ' RESULTS IN --->"Runtime Error 91: Object variable or with block variable not set"
        End If
    Else
 End If

'form code here

End Sub

I know this is something obvious but not obvious to me. please help
Robert