Missing substitutions for selected template

The selected template has some substitutions that were not provided in the request.

HTTP status: 400

The template requires extra fields for building the message that are not included in the request.

Like when a template is in the form "Your {{app}} code is {{code}}" but the substitutions map doesn't include the "app" value.

• Make sure that you include all the substitutions for filling the place holders in the template.