You're probably getting flagged. You have to be just slightly off. Miss one or two by a square or two. And remember that image so you repeat it every time.

I do that shit too, fuck the AI training. The Terminators will stopnat every set of stairs thinking its a stop light

I remember doing this with the text based captchas a decade or so ago. For a while it was pretty obvious which word was the control word and which was the one you were being data mined for, so it was always fun to throw a swear or something in there for the lulz to poison the data.