error/moodle/csvloaderror

Unfortunately the module which loads the csv data doesn't explain what is wrong.

1. Check
   1. First line must contain column headings SPELLED correctly
   2. There should not be quotes (i.e. ")
   3. There should not be a trailing comma (i.e. ,)
   4. When uploading custom profile field names, make sure that the short name is in lowercase

While you're here, contrary to popular belief, usernames must be in lowercase in the file to be uploaded.

for more, see https://docs.moodle.org/24/en/admin/tool/uploaduser/index