my endnote x8.2 is not working anymore with my word 2016 mac. PLEASE HELP

endnote is not syncronizing with word. I added a reference to the software but when I try to add it on word it doesn’t find it. The strange thing is taht I can see that I still have 236 reference on the sofwtware but on the account online they are still 237…it doens’ matter if I sync. please help