Did you mean to paste in your list of columns? Looks like you might have forgotten it. 
For example, something like:
firstname,lastname,username,email,cohort1
You might want to open your file in a text editor and see what it looks like. The Moodle docs page has some notes about how to make your spreadsheet program output a better CSV: https://docs.moodle.org/37/en/Upload_users#Spreadsheet
And are you asking about the "Upload users" page, or "Upload cohorts"? https://docs.moodle.org/37/en/Upload_cohorts
- Ray
firstname,lastname,username,email,cohort1
You might want to open your file in a text editor and see what it looks like. The Moodle docs page has some notes about how to make your spreadsheet program output a better CSV: https://docs.moodle.org/37/en/Upload_users#Spreadsheet
And are you asking about the "Upload users" page, or "Upload cohorts"? https://docs.moodle.org/37/en/Upload_cohorts
- Ray
