Hi, that’s because you just mapped them as areas instead of placing a node on the highway.
You should delete these areas and do it as recommended in https://wiki.openstreetmap.org/wiki/Tag:highway%3Dcrossing
Anyway, thanks for figuring out these warning actually mean something and asking for help. If all inexperienced mappers did that, we would have much less stuff to clean up
However, by not using an area, there is no geometry data captured on the map. Is there a way to associate a polygon with the pedestrian crossing? If so is there some way to have it rendered on the map?