If you open the CSV import wizard and get an access-denied error, your account simply isn't enabled for CSV import yet. You're not doing anything wrong — CSV import is gated, and most accounts don't have it on by default.
What the error looks like
When CSV import isn't enabled for you, the wizard returns an access-denied response (HTTP 403) with the code cohort_locked. Every step of the wizard except downloading the template is gated, so you'll hit this as soon as you try to upload.
Why it's locked
CSV import is a Phase-1 feature, available to a paid/operator-managed cohort while we finish hardening it. Access is granted by allowlist rather than by self-serve toggle, so it's on for a specific set of accounts and off for everyone else by default.
How to get access
Contact support to ask about eligibility and the upgrade path for CSV import. Let us know your seller ID and roughly how large a catalog you want to import, and we can tell you whether your account qualifies and enable it if so.
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