Instagram: "400 session invalid"

A 400 session invalid from Instagram means the access token Postbean holds is no longer accepted. The connection was fine when you made it; something has invalidated it since.

Why it happens

• The token expired. Instagram tokens are long-lived but not permanent. Postbean refreshes them automatically, but a token that goes unused for long enough expires anyway.
• You changed your Instagram password. That invalidates every issued token.
• You removed Postbean from Instagram’s Apps and websites settings.
• The account type changed back to personal — the business permissions go with it.
• Instagram forced a re-login after a security event on the account.

The fix

Reconnect the channel:

1. Open Connections (/panel/connections).
2. The Instagram channel is marked as needing to be reconnected. Click Reconnect.
3. Sign in on Instagram and approve every permission again.

Anything still scheduled to that account publishes normally afterwards — the channel keeps its identity, so nothing in your queue is lost. Posts that already failed while the token was dead need to be republished.

Making it happen less

• Keep the account Business or Creator.
• Leave Postbean in place in Instagram’s Apps and websites settings.
• After changing your Instagram password, expect to reconnect.

If the error comes straight back after a successful reconnect, that is not a token problem — write to support@postbean.app with the post link and we will look at the API response.