Check the reason first
Temporary restrictions, unavailable providers, and incomplete responses can all leave a check inconclusive. Read the reason and check time before deciding whether another attempt is useful.
Choose a review policy
Keep unknown records separate. For an interactive signup, an ownership-confirmation step may be appropriate. For a campaign, decide whether the audience should wait for review. Do not relabel the whole segment as invalid.
Avoid repeated blind retries
Immediate repeated checks can add load without producing new evidence. Follow documented retry guidance and keep an attempt limit.