Hey, thanks for the report. This is a known issue. The OAuth token used by Slack automations doesn’t have the required scopes (chat:write, channels:read, etc.). This is a bug on our side, so there’s nothing the user can do to fix it.
A few other users are seeing the same thing too: Slack automation failing with missing_scope error.
The team is aware. I can’t share an ETA yet, but your report helps us prioritize. I’ll post an update here when we have news.