EndNote is creating multiple copies of my citations

I am using EndNoteX2 on windows vista, Microsoft Office 2007.

THe problem that I am having is that everytime that I add a new citation “cite was you write” another copy of the previews citations is added to plus the new one. 

“…leaving out decline of marine mammal stocks caused by depletion of food sources, predation, climatic changes, habitat degradation and diseases (Taylor et al. 2007)(Taylor et al. 2007)(Taylor et al. 2007)(Taylor et al. 2007)(Taylor et al. 2007)(Taylor et al. 2007)(Taylor et al. 2007).”

So each time I cite something along my paper another “taylor” citation is added, the ploblem applies to all the citations made on my paper.  I already started another document from zero and the problem does not go away. 

How I can fix this? I need to defend soon and I spend more time trying to fix this than writting my thesis.