That's a glitch that's effecting some devices since 3.2. The easy work around is put the 2 finger touch hack on (it just involves dropping a file on the device, pretty simple to do) your HD and it will be back to proper turns. You'll find it in the Kobo developer sub-forum above (see here:
https://www.mobileread.com/forums/sho...d.php?t=232431). Just make sure you uninstall it before you upgrade again as some people had a problem with the 3.2 upgrade if the hack was still installed.