Can't remove existing ground

Hi all,
i’m starting to rebuild existing airport and i can’t remove some existing grass polygone on the satellite image.
I first add a polygone for excluding all from existing airport, but some grass stay in place.

this is a screen capture of my polygone result in red my new runway and this green patsh i can’t hide :

I can’ see origin satelite image below it…

Any one know why ?
thank’s for hour help.

You have Bing and Programmetry switched off. How does it look when you switch them on again ? This “green grass” looks like raw 2d satellite imagery… but maybe it is just the bottom ? Is it flat everywhere ? Your poly did have an effect…it clearly crosses and removes the AI boundaries within a certain margin…

Hi ArcanePython9312 !
Thank’s for your answer.
Yes that’s the tric. Bing Data are switched off after a bad connexion and don’t switch in back with my test.
I switched it in and i can now see originale satellite after my polygon exclude automatic airport volumes.
Thank a lot.
Bye