Cher, the override(s) would be anything on the body page(s) that isn't the same as what is on the corresponding master page. So for example if you had changed the size of the text frame on the body page (e.g. by inadvertently resizing it or dragging it out of location on the page), or adding graphic items such as callout arrows that aren't inside another graphic frame.
I do understand wanting to know what the override is, rather than just blowing it away, so that it won't be inadvertently repeated.
Do the next step only after having a backup of the file safely tucked away....
One more thing that I've seen happen, btw, is that somebody has inadvertently created empty text frames on the body page -- one particularly memorable file had literally dozens of them sprinkled around the page. To see if there are any of those, click on the margin of the page, outside the body text frame, so that nothing is selected. Then do Ctl+A to Select All. Carefully note how many objects are visibly selected -- on straightforward text content pages it would likely be just your regular body text flow.
But if you see more selected, then carefully click on the "good" objects to deselect them one by one. You might have to use the Graphics > Bring forward command to bring the object in front if it's hiding behind something else.
Another possibility is that object(s) have been inadvertently dragged off the page, so that even though you can grab them by doing Select All, you don't see it visible. There are a couple of ways to get it back on the page, but I'll leave that for another posting.