Date column changes when I upload a shapefile with this column type to Google Earth Engine

I have a FeatureCollection in my Assets in Google Earth Engine, which is the result of uploading some shapefile containing some productive areas from the company I work for.

When I import this collection to my script and print it, I can see the columns which contain date values in the previous shapefile are now changed to type Long in the FeatureCollection.

How can I import this FeatureCollection without having this problem?