When you log back into TurboTax Online and open up your return, it should open back to the previous page that you were working on. If it’s not doing this, please clear your browser cache (or use a different browser), and try again. This FAQ has instructions on how to clear the cache in several popular browsers: https://turbotax.community.intuit.ca/community/tax-topics/help/how-do-i-clear-my-cache-browsing-history/00/873530
You also may be opening up a different copy of your return, if you have started more than one or made copies.