In your email client, there is an option or a button to “Show Message Source Code” or something similar, click it and send me the content of that option to [removed] (email removed to avoid spam) this will help me with the investigation.
By default, the plugin sends the alerts using the plain text format, something that all email clients understand, there is an option to change the format to HTML to include colors and images which most email clients understand, but they render the content in different ways which makes it difficult for developers to test, this could explain why you are seeing just a blank message.
I haven’t received the copy of the blank mails that you are receiving.
Marking as resolved, feel free to re-open if you can provide more details.
