I've been using it forever and last couple of weeks, cannot rotate only one page. when I rotate, the whole document rotates. can you help?
Rotate the page, don't rotate the view.
Chances are you are rotating only the view and not the actual pages. I assume once the complete document rotates, you save the document and re-open it, the original rotation is back. There are two ways to rotate in Acrobat: One is to rotate only how the document is currently being displayed - the "View". This rotates the view for all pages, and will only be temporary. Then there is the rotate pages command which will rotate one or more pages, and that rotation is permanent: Tools>Pages>Rotate or right-click on a page in the thumbnail view and select to rotate from that menu.