You may have uploaded a full page graphic to your ad journal that doesn't meet the 1000px x 670px dimensions of the ad area. In order that it looks right, you may want to add some "padding", or spacing above the graphic.
How to get there:
Login to your Wizadjournal back end account.
Click on the "Ads" tab.
Click on the first action item, "edit" (pencil icon).
What to do:
Under "Design Option", please select "Ad Graphic Full Page", if you haven't already.
Decide how much spacing or padding you'd like to surround your ad and enter it under "Padding on Top", then click the "Apply" button.
Click on the "Refresh" button to review.
Then, click "Save ad" to maintain your changes.