Can we attach PDF's which are saved in local drives in my laptop or has the PDF's need to be stored in a website? I need to send individual PDF's to a user and another PDF which is relevant to another user. I can send normal PDF's to users without no issue using whatsapp cloud API. I tired uploading all PDF's to dropbox but that also didnt work. So any help on how we can upload my PDF's to website which is secure but can be used to send as whatsapp messages.