We had that happen before too, at least similar. The warning popped off in the dashboard, but it didn’t brake.
We put it down to an insect potentially hitting the sensor bang on. I’m not saying/implying it hasn’t happened to you, i’m just saying that it can’t have been the shadow since a radar doesn’t pick up colours, only “objects”.
Prior: SEAT Ateca Xcellence Lux 1.5 TSI DSG MY19, VW Golf GTE PHEV DSG MY23
Current: Hyundai Ioniq 6 Ultimate
Next: we'll see what's available in 2028.