This means the add-on can't find the recipient email address to send the mail merges to. If you are using G Merge Plus automatic columns, G Merge Plus will automatically map the column Shared to / Recipient Email.
To map your own header columns, please:
- Turn off the automatic columns slider at the bottom of the sidebar. This allows you to customize the settings for your mail merge.
- Make sure to specify a column for the "Recipients" field or type in the email address by selecting * SPECIFIC USERS * in the dropdown list
Once the above changes are done, clear out the G Merge Plus status cells marked "Done Email not sent, no recipient" for the rows you wish to reprocess then click Generate > Now.