Using MS Word 2016. When I click to add footnote to any word on the final line of text on a given page, it puts the footnote text on the following page.

The footnote reference number in the text body, and the footnote text, must be on the same page. At least the footnote text must begin on the same page as the footnote reference number in the text body. If the entire footnote text doesn't fit on that page it is fine, but it must begin on the same page as the footnote reference number. If there isn't enough space for this to occur, then MS word should push that line of body text to the following text so that the footnote reference and the footnote text will coincide on the same page.

What is the solution? Is this a bug in the program?