whatsapp changed it files location from internal storage > whatsapp to
internal storage > android > media > com.whatsapp > whatsapp
& Google official Android restrict any other app to perform any action in Android folder only the app with primary string & manifest can do this.
but as gallery or file mannager isn't only what'sapp so it can't access those folders yes file mannager can but still you can see it via file mannager only not via gallery
so you can't see those
But there is a workaround. Backup all your data on Google Drive in your dual messenger whatsapp number. Then, install WhatsApp Business from Play Store and sign in with that number and restore the backup previously made.
Lastly, disable Dual Messenger.
You will now be able to view pdf files on your new WhatsApp Business account.
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