ERR_BANK_SYNC on Xero: Bank sync disconnected. Root cause: The bank feed connection has been interrupted or the authentication credentials used to access the bank's open banking API have expired. Banks periodically require re-authentication, and some banks revoke API access after extended periods of inactivity or following security updates to their online banking platform. Step 1: Check connection. Verify bank connection active Step 2: Re-authenticate. Log in to bank again Step 3: Check bank status. Verify bank online Step 4: Retry sync. Force manual sync