|There are two commands for removing files.|
PURGE & DELETE
Purge will remove multiple versions of a file and save the latest version.
PURGE/KEEP=n file ( will save n copies of the requested file )
In your case, a PURGE would be the first command to use.
If this command doesn't help you, you need to investigate the disk file by file to determin what files to delele......
$ HELP PURGE
$ HELP DELETE