[Recipient_1:Email]: No hay ningún encabezado de correo electrónico obligatorio.

@mauricio_5339 This message almost always means that Acrobat Sign is looking for a very specific column name in your CSV file to identify where your recipients' email addresses are located. Even if the emails are clearly there, the system needs that exact header, like "Email" or "Recipient Email" (Adobe's exact requirement can vary slightly based on the feature you're using, so it's good to check their help documentation for the specific bulk sending feature you're using), to understand which column contains the crucial information. It's a really common hurdle when setting up these kinds of automated processes, and it's completely understandable to feel stuck when you encounter it. https://helpx.adobe.com/sign/using/mega-sign.html