Water does not drain from the flat roof of the garage

Exception: green roofs with retention irrigation - but you didn’t buy that and certainly didn’t receive it.

I agree. The requirements are not described here.

In principle, a good idea with the greening. But if it does not drain, then that is a defect. Possibly consult an expert?!

Slope is standard and therefore mandatory. Have it corrected or accepted as is; document properly and refuse payment etc. classic approach. It is a defect and is reported.

Here is a visual update of our garage roof. You can clearly see the damage standing water causes within a year. About 3 weeks have passed since the last rain. It takes that long for the water to evaporate.

Why was the defect not corrected?