When you import the Admissions CSV file at Admin > Students > Admissions, if your file is missing the column headers in the first row of the spreadsheet then the importer will take the first student to be the header and miss them out. Make sure you go back into the CSV and insert a row at the top with the following headings:
If you have already imported the CSV file, you can manually input that missing student's details at Admin > Students > Add Student Manually.
