Is the IKEA METOD base cabinet only extendable by 20 cm?

Hello,

I have 2x the 20cm wide, extendable Metod base cabinets in my new kitchen.

After assembly, I have the following problems with both:

- The drawers do not close completely, they remain about 2cm open. This is because there is a plastic part installed at the end of the drawer hinge, over which the drawer only slides with force. Only when I push the door with force does the cabinet close properly. Is this normal? Or can this plastic part be removed? The strange thing is that it is the same with both cabinets. I thought it might be a material defect, but twice is not normal, right?

- The other problem with the cabinet is that I cannot get any stability in the drawer. Everything is screwed tightly, and the metal shelves are correctly inserted. Still, the door and the drawer are very wobbly when pulling in and out. Does anyone know what could cause this?

A friend of mine also installed this cabinet, but he does not have these problems. He also has the plastic part at the end of the drawer hinge, but the drawer slides over it smoothly with him. And his drawer is not as wobbly as mine, even though it is assembled the same way.

Does anyone possibly have any advice for me?

Thanks a lot!

Some reading can be found here:
Regards,
IKEA-Freund