I am trying to create a map that visualizes the attendees of a meeting based on their zipcodes, but for some reason the CSV file I am using that has the zip code and attendee data won't load into ArcGIS online properly. Whenever I try to add it as a new layer from the CSV file, it won't let me change the location settings to show that the file contains zip code information. It only lets me organize it by latitude and longitude, which is not data I have in the CSV file. How can I get it so that the location settings allows me to group my data by zip code instead of only by latitude and longitude and create a new layer in my map? 
