Integrations disconnect when the OAuth token or API key becomes invalid — usually a password change, revoked app access, expired token, or rotated key on the other system's side. The signature is a sudden sync stop with 401s in the log.
Identify the cause
Settings → Integrations shows the disconnected connection and its last error. 401s point to invalidated credentials: someone changed a password, revoked OAuth access, deactivated the connected user, or rotated the API key on the source system.
Reconnect
Click Reconnect and re-authorize via OAuth, or paste the new API key. Using a dedicated service account (rather than a personal login that can leave or change passwords) prevents most repeat disconnects.
Prevent recurrences
Connect integrations with a service account whose credentials don't change with staff turnover. Where the source system expires tokens on a schedule, note the cadence so you can reconnect proactively. Rotate keys with overlap (see Authentication and API keys).
After reconnecting
Trigger a manual sync and confirm the last-sync timestamp updates and data flows. Check whether anything changed during the outage that needs a catch-up sync — the nightly full diff will usually reconcile it.
