Authentication can fail separately from browsing or existing sessions. Note whether already-signed-in devices still work, whether password reset loads, and whether the app and website behave differently. Check the exact error and time.
Do not repeatedly reset a password during a suspected outage unless you have evidence of account compromise. Compare official status and recent reports of the same login symptom. If only one account is affected, use the service's official support path rather than calling the whole service down.
A partial failure needs a precise report: “new sign-ins fail; existing sessions work.”
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