Certain PDFs displaying strange characters

Hello,

I have a user who was sent a PDF. When opening it in Adobe, when viewing it in the web browser, and when viewing it in the Outlook preview function, it displays weird characters instead of the standard Arial font that is being used. I have checked for updates on Adobe and the system and it is fine. I have sent the PDF to myself and others and it is viewed fine. I attached screenshots of what it looks like and what it should look like.