Since it has a DADF, there should be a scanner for both sides of the page in one feed. So look on the underside of the scan lid and make sure there isn't a sticker or something covering the scanner.
As stated, your model isn't in North America, so I cannot in any way consult one here to see, but ADF and DADF are standards, so it should be similar to devices I have here.
So here is a picture of one such DADF, I'm guessing that on yours, the top portion I have circled is covered in some way.
