In spite of the incredibly frustrating responses from these techs -- who appear to not thoroughly look at the informative pleas for help by repeatedly asking questions already answered in the inquiry...
I have found an amazingly Simple solution!!....
Go to Settings > device maintenance > storage > documents > select (all pdf and others you don't want) > delete.
That's it!! So simple!! Less than 2 minutes! Done!!
.... and I am a 55 yr old country bumpkin with absolutely NO computer or tech training!!!