You can easily disable the mark as sent on email/whatsapp option in Moon Invoice by following the steps below.

1. Open the Moon Invoice application on your device or tap on this link.
2. Navigate to Settings ➜ App Settings.
3. In the Proforma Invoice ➜ Print & Email section under Mark as Sent on Email/WhatsApp, toggle it off as needed.
4. Click Save to apply the changes.