Hi @MARKLIGON ,
Could you please share a screenshot of your flow's configuration?
First please check the status of the connection, make sure the Status is Connected.

Then check if the account you have selected of the 'Send an email' is valid.

As the error message said, there is some issue about the configuration of the 'Send an email' action.
Perhaps it's not caused by the connection.
Best Regards,
Community Support Team _ Zhongys
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