Templating with netlify email addon doesn't works

Hello,

The variables of my email template are not replaced when I use the sendEmail function.

template

<html>
    <head>
        <meta charset="utf-8">
    </head>
    <body>
        <p>Envoyé par {{sender}}</p>
        <h1>{{contactSubject}}</h1>
        <p>{{content}}</p>
    </body>
</html>

My code:

import { sendEmail } from "@netlify/emails";
//...
const requestBody = JSON.parse(event.body) as SendMailDto
console.log("requestBody", requestBody);

await sendEmail({
        from: process.env.EMAIL_FROM,
        to: process.env.EMAIL_TO,
        subject: "SRR - Formulaire de contact",
        template: "contact",
        parameters: {
            sender: requestBody.email,
            contactSubject: requestBody.subject,
            content: requestBody.message
        },

    });

The console log show that the object is well filled. But I receive this in my inbox :

PS : it works from this interface. The template is hydrated in the preview section and too in the final test mail in my gmail account.

Can you share a minimal reproduction as a repo?