Passing object as parameter throws compile error - Type Mismatch

While using VBA, When passing object as parameter throws compile error.

Sub layoutAnArticle()

Dim myWordDoc As String

Dim myDocument As InDesign.Document

Dim myStory As InDesign.Story

Dim myTextFrame As InDesign.TextFrame

Dim myPage As InDesign.Page

Set myInDesign = CreateObject("InDesign.Application.CS6")

Set myDocument = myInDesign.Open(workingDirectory + workingFile)

Set myDocument = myInDesign.Documents.Item(1)

Set myPage = myDocument.Pages.Item(1)

myboundsarray = myGetBounds(myDocument, myPage)

Set myTextFrame = myPage.TextFrames.Add

myTextFrame.GeometricBounds = myboundsarray

myTextFrame.Place ("ScriptingTryWordDoc.docx")

Set myStory = myTextFrame.ParentStory

formatStoryText (myStory)

end sub

Sub formatStoryText(ByRef subStory As InDesign.Story)

myInDesign.FindGrepPreferences = idNothingEnum.idNothing

myInDesign.ChangeGrepPreferences = idNothingEnum.idNothing

myInDesign.FindGrepPreferences.FindWhat = "  +"

myInDesign.ChangeGrepPreferences.ChangeTo = " "

subStory.ChangeGrep

myInDesign.FindGrepPreferences.FindWhat = " *\r[ \r]*"

myInDesign.ChangeGrepPreferences.ChangeTo = "\r"

subStory.ChangeGrep

myInDesign.FindGrepPreferences = idNothingEnum.idNothing

myInDesign.ChangeGrepPreferences = idNothingEnum.idNothing

' end of formatStoryText

End Sub

While trying to run layoutAnArticle, it gives "Compile error: Type mismatch..." at the calling point of formatStoryText.