Mail Merge creates blank document
After choosing an envelope template, I create a merge text box filled with data from a Numbers document. When I select Mail merge from the Edit menu, I'm prompted to choose the mail merge source and then I choose to create a new document (in stead of printer). The new document is created and opens to reveal my, say 30 envelopes, are now 60 envelopes. There is a blank envelope in between each envelope I've created. Trying to delete every other envelope doesn't work as it appears to be linked, therefore, deleting the one I created as well as the blank one.
What is it I can do to prevent the creation of the blank envelope in between the actual document?
Thank you.
MacBook Pro, Mac OS X (10.6.7)