Here is a tutorial from the user Dedel from the german forum spyderforum.de: You can adjust the handlebar, unfortunately some dealer don't check the screw for tightness.
If you look from above at the middle of the handlebar you can see a black plastic cap, which once remove, so you can reach the screw. Remove the screw, push it from bottom to top against the handlebars or slightly hit it until the handlebars are loose, then you can readjust it.