My automated WhatsApp PDF-sending script worked perfectly for the first two messages, but now it refuses to attach any PDF at all. The text portion still sends; the file simply never shows up in the chat. This happens with every PDF I try, regardless of size or content. I need the underlying issue identified and corrected so the tool can reliably attach and send PDFs again. Once fixed, please verify the solution by sending multiple test PDFs and share a concise change log so I can understand what was adjusted and why.