Here is what could be causing this error message :
1. Make sure you are using our recommended census template - check out our help center article to download the template
2. Did you export your file as a ".CSV" (comma separated values)? Follow these steps to export as the correct format.
3. Did you double check your census information? Make sure: -Birthdates are in the correct format (MM/DD/YYYY) -ID numbers correctly reflect grouping of subscribers and dependents -Coverage tiers are entered correctly: employee, employee_spouse, employee_child, employee_children, family or waiver