Formatting bibliography

I am using Endnote X2 and Word (for Mac) 2008. 

I have set my bibliography to format it as optima font size 12, but although the first couple of references come out as optima font, the rest of the references come out as helvetica font which is the default font of my endnote library (I don’t think I have ever muddled with that). I have unformatted and reformatted to no avail. I wonder whether anyone can help me. Thanks!!