Oracle impdp onlu one schema when expdp its use many schemas

I have the following problem and doubt in Oracle … I am trying to import with impdp a save from my database made in which I export several schemes … the problem comes when I try to import into the same database in another scheme completely empty one and only one of those schemes that are in the export (expdp) …. during the import show several errors of creation, of sequences, of data that already exist and of creation of other objects in general. How is this possible if the scheme where I import this empty? the expdp I execute it in the following way:

To export: 

expdp \ "/ as sysdba \" DIRECTORY=logic_bakups DUMPFILE=backup%U.dmp FLASHBACK_TIME=timestamp PARALLEL=5 SCHEMAS=SCH1,SCH2,SCH3,SCH4

To import:

impdp \ "/ as sysdba \" DIRECTORY=imp_logic_backups DUMPFILE=backup%U.dmp PARALLEL=5 REMAP_SCHEMA=SCH3:SCH3_V2 REMAP_TABLESPACE=source_tablespace:target_tablespace_V2

Thank you