Field Information Disappearing

When creating a new reference, I save every time I enter information into a field.  Despite this, when I’ve finished and want to see the summary view, the data that I entered is often missing.  This seems to happen more often if I do a copy/paste - such as pasting an article title or URL.  I wondered if anyone else is having this problem or whether I’m just doing something wrong.  I’m using Windows 10, EndNote20