Hello,
At this time, a user context (OAuth token obtained via a user oriented OAuth flow) is necessary to send internal chat messages.
It is not possible to send an internal chat message using a Client Credentials Grant OAuth token (i.e. not possible to send an internal chat message via a Data Action).
You can check for existing Genesys Cloud ideas or create one and vote for it here: https://genesyscloud.ideas.aha.io/
Regards,
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Jerome Saint-Marc
Senior Development Support Engineer
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