The following are a list of things you can try to troubleshoot when the journal titles are not abbreviated. For additional support please contact the library at medlibrary@ucf.edu, or your personal librarian.
First: Make sure Word is updated.
Second: Make sure you are not saving the EndNote library to cloud storage. Saving an EndNote library to cloud storage may corrupt the library.
Third: Delete terms list and reinstall, see directions at https://support.clarivate.com/Endnote/s/article/EndNote-20-Generate-full-or-abbreviated-journal-names?language=en_US
Fourth: Perform a field codes clean-up; instructions available at https://support.clarivate.com/Endnote/s/article/EndNote-Problematic-field-codes-causing-jumping-cursor-the-range-cannot-be-deleted-or-other-problems-while-formatting?language=en_US
Fifth: Try a new Word document