Workflow Email Actions do not allow you to select or assign a specific Invoice or Document to the email. Since there isn't an Invoice or Document associated with the email, the Merge Field has no source from which to retrieve the information.
This limitation applies to all document types, including invoices and proposals.
When creating Email Templates for use with Workflows, we recommend avoiding Invoice and Document Merge Fields.
Additionally, always review your email templates to ensure they are free of unsupported merge fields to maintain professionalism in automated communications.
If you need to include a specific Invoice or Document link, a common workaround is to create a Task in your Workflow as a reminder to send the email manually. You can then add the appropriate link when sending the email.
If your Email Template includes a Document Merge Field for a document or invoice link, the field will appear blank when the email is sent through a Workflow.
Alternatively, if you prefer to keep the email as an automated Workflow action, consider removing any document-related merge fields from the email template. This ensures that the email does not contain blank fields.
What about Event Merge Fields?
Event Merge Fields are supported when used with Workflow Email Actions. However, there is an important limitation to be aware of.
If a contact has multiple Events, the Workflow will automatically use the Event with the earliest start date and time when populating Event Merge Fields. You cannot manually change which Event the Workflow uses.
If multiple Events have the same start date and time, the Workflow will select one of those Events at random.