Is any of the tyre flat? >>let's pump up
If no, Please check inside the steering unit (the black plastic cup).
1 (or 2) of the 2 columns guiding the steering wire may be damaged.
Also, wire may be too tight.
click to video
To take the black cup off, undo these 2 screws.
You will have to take the steering metal bar first.
Use the zipper plastic bag to keep the collars and screws,
so that you won’t lose them.
When COGY is new, the column looks like this.
After using it for a while, the columns show wrinkle like pattern on the surface, which is still OK.
When this damage gets bigger and deeper, the wire movement will be heavy,
accelerating the damage.
Contact Koko (firstname.lastname@example.org) for replacement collars,
before the screw also gets damaged like this.
In order to undo the screw-nut that are holding the collars in place,
you may need a 7mm spanner and a screw driver (+ shape)