Does anyone have a Joolz Aer+ pram?

How do you partially recline the seat back? I currently have it in full recline mode so it's completely flat, and I know how to push the seat up to make it completely upright (zip it up), but in the photos and manual it looks like it will go halfway up. The manual is so vague and is all diagrams with no text and I even emailed Joolz customer service but no one has go back to me 😅 is it even possible to have it half up in partial recline? If so, can someone tell me how 😂