VBA rule + script run on manul testing but not automatically

I have the following VBA script that I have setup along w/ a rule in Outlook 2016. The rule + script works correctly if I go to Rule Wizard and run manually but doesn't trigger when new mail comes in and rules should be running the script. I found various references to similar issue that mentioned I need to change the Trust Center setting so I have changed Macro setting to Enabled all.

p.s. I think this issue is not related to the code as all but related to how Outlook rule trigger VBA script

Code:

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Sub filter(Item As Outlook.MailItem)
    Set Reg1 = CreateObject("VBScript.RegExp")
    Reg1.IgnoreCase = True
    Reg1.Global = True
    Reg1.Pattern = "foo"
    If Reg1.Test(Item.Subject) Then
        strSubject = Item.Subject
        Item.Subject = strSubject & "bar"
        Item.Save
    End If
End Sub

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