Cannot use a Zoho Form in CRM Email Template

Cannot use a Zoho Form in CRM Email Template

I've created a Zoho form that has integration with Zoho CRM and is linked to a custom module. I know the form works as I have tested it.

When I try and insert this Zoho Form in a button on a CRM email template set up with the same custom module I get the error: "You have not created a form for this module yet. Click here to Create New Form"

Any idea what I'm doing wrong?