Drop pluggable database not remove datafiles

Hello, 

In my daily development flow we're cloning PDB.

From time to time we are unable to clone db cuz errors:

ORA-27040: file create error, unable to create file

[2023-12-13T21:34:34.405Z] OSD-04002: unable to open file

[2023-12-13T21:34:34.405Z] O/S-Error: (OS 5) Access is denied.

What we do

Set all data files to offline by:

ALTER DATABASE DATAFILE 'db.DBF' OFFLINE FOR DROP

and next drop db by

DROP PLUGGABLE DATABASE DB INCLUDING DATAFILES;

Unfortunately this command does not remove files and these files are still used by OracleServices ( I have to manually restart service )

I do not see these files in any oracle dictionary