I had a similar problem with dates transformed in datetime
In Arc Gis Online, I fix the date and format it by removing the time on the map. And it works fine on the map and in the pop-up
But, In Experience Builder with the map already fixed it shows again the same datetime (See figure)
An additional problem in Experience Builder to the numbers is one point every three digits and I have not been able to eliminate them (See Submission in the figure)
Please I need help on these issues