Intermittent 462 Error when Using Word - vba

Question

I have the most baffling set of errors cropping up in my code. The goal is just to create a Word document from a template, and edit the document using find/replace to fill in some data from excel. Here are the symptoms:
When I run the code the first time, everything works perfectly
The next time I run the code, one of two thing happens depending on what I did before calling it:
If I closed the word document before running the code again, the second time I run it (and every even-numbered run after that) it fails. This happens even if I've closed the userform and reran the code from the VBA editor. I think this has something to do with binding the word objects, but I'm new to VBA and don't see what I've done wrong.
If I didn't close the word document and just press the button again, the code runs and it spawns a new document, but that must not be set to the active document because it just edits the first document I spawned again.
This is the offending code:
Private Sub Generate_Click()
Set wordApp = New Word.Application
wordApp.Visible = True
wordApp.Documents.Add Template:=ThisWorkbook.Path & "\Template.dotx"
FindReplace "[[[DATE_TAG]]]", DateBox.Value
FindReplace "[[[SHIPPING_TAG]]]", POBox.Value
' ... and more of that ...
Set wordApp = Nothing
End Sub
Sub FindReplace(find As String, replace As String)
With Word.ActiveDocument.Range.find ' <---- This line is where the debugger points
' on the 462 error
.Text = find
.Replacement.Text = replace
.Wrap = wdFindContinue
.MatchCase = True
.MatchWholeWord = True
.Forward = True
.Execute replace:=wdReplaceAll
End With
End Sub

Answer 1

In Generate_Click you create an instance of Word referenced by the variable wordApp, but that variable isn't included in the scope of the called Sub FindReplace.
To resolve this you have options:
Create a global variable to reference the Word instance (which would also be accessible to FindReplace) or
Pass an additional parameter to FindReplace via which it can use that Word instance without requiring a Global variable.
Try this instead:
Private Sub Generate_Click()
Dim wdDoc as Word.Document, wordApp As Word.Application
Set wordApp = New Word.Application
wordApp.Visible = True
Set wdDoc = wordApp.Documents.Add(Template:=ThisWorkbook.Path & "\Template.dotx")
FindReplace wdDoc, "[[[DATE_TAG]]]", DateBox.Value
FindReplace wdDoc, "[[[SHIPPING_TAG]]]", POBox.Value
' ... and more of that ...
Set wordApp = Nothing
End Sub
Sub FindReplace(wdDoc as Word.Document, find As String, replace As String)
With wdDoc.Range.find
.Text = find
.Replacement.Text = replace
.Wrap = wdFindContinue
.MatchCase = True
.MatchWholeWord = True
.Forward = True
.Execute replace:=wdReplaceAll
End With
End Sub