iOS share menu, Share PDF to Whatsapp

I have a PDF file saved to Files. Via Files, I select the pdf to be shared, opens the system share menu and then I select to share to Whatsapp, nothing happens.

If I open Whatsapp directly, I can attach and share the file correctly.

I'm on the latest iOS 17.3.1, latest Whastapp version, the PDF file is barely 2mb. I need to know why is the native share dialog not working for this PDF file as it is impacting a workflow in one of my business apps. The file was generated by my app, but it also cannot be shared to Whatsapp via the share dialog menu, but since it is also happening in Files I assumed its not a problem with my app.

For additional info, the same file can be shared to Slack & Telegram with no issue via the native share dialog menu.