This can be caused by the fact that there is a drawing canvas somewhere in the document.
When you insert a drawing, such as a text box, a drawing canvas object is created around this text box. To solve this problem, make sure that all drawing objects are not drawn inside of a drawing canvas.
Turn the drawing canvas on or off
- On the Tools menu, click Options.
- Click the General tab.
- Select or clear the Automatically create drawing canvas when inserting AutoShapes check box.