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- Go to the Project settings page → Workflows → Actions → click Edit.
- Go to Validators on the selected transition → click Add condition.
- Locate SLA metric state validator by SLA PowerBox → Add.
- Select the SLA metric.
- Pick the SLA state(s) in which the validator is True.
- Add the message to be displayed in case of validation failure (optional).
- Click Add and publish the workflow.