Adding message and loop to input box password

[freetimefost]

I'm trying to add a message box if an invalid password has been entered into the below, but keep getting a runtime error, any ideas on how to fix this?

Runtime Error 13
Type Mismatch

Thanks

Private Sub Workbook_Open()
Do
pword = InputBox("Please Enter Password")
If pword = ThisWorkbook.Sheets("Passwords").Range("B4").Value Then
    Statement = True
    Sheet3.Visible = True
    Sheet3.Unprotect ("blue")
    Sheet3.Select


ElseIf pword = ThisWorkbook.Sheets("Passwords").Range("B5").Value Then
    Statement = True
    Sheet4.Visible = True
    Sheet4.Unprotect ("yellow")
    Sheet4.Select
    
ElseIf pword = ThisWorkbook.Sheets("Passwords").Range("B6").Value Then
    Statement = True
    Sheet5.Visible = True
    Sheet5.Unprotect ("red")
    Sheet5.Select
    
ElseIf pword = ThisWorkbook.Sheets("Passwords").Range("B3").Value Then
    Statement = True
    Sheet3.Visible = True
    Sheet3.Unprotect ("blue")
    Sheet4.Visible = True
    Sheet4.Unprotect ("yellow")
    Sheet5.Visible = True
    Sheet5.Unprotect ("red")
    Sheet1.Visible = True
    Sheet1.Unprotect ("admin")
    Sheet1.Select
ElseIf pword <> ThisWorkbook.Sheets("Passwords").Range("B:B").Value Then
MsgBox "Incorrect Password Entered. Please Try Again"
End If
Loop Until Statement = True
End Sub