This error means there is something off with the access to the Google Sheet used in the custom metric within the rule.

1) Please go open the Google Sheet used for your custom metric within the rule, and open its sharing settings. Make sure the access is set as "Anyone with the link":
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2) Go to Automate -> Custom metrics. Open the custom metric used in the rule -> Google Sheets:
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Click the gear button as on the screenshot below, copy and paste the link from the Google Sheet, click Add -> Save changes

3) Once you have reconnected the Google Sheet to the custom metric used in the rule, wait for the next check of the rule. Given that the access issues have been fixed, the error should disappear from the logs during the next сheck.

If the issue persists after completing all the steps above, please reach out to us at support@revealbot.com