400
checkout.bad_cursorcheckoutThe pagination cursor is not valid
Returned by the implementation; no specification rule declares it yet.
Cursors are opaque and are only ever valid as returned. A modified, truncated, hand-built or stale cursor is refused rather than silently reinterpreted.
Why the API refuses
cursor is not valid
What to do
Pass next_cursor back exactly as you received it. If you are storing cursors between sessions, do not — request the first page again instead.