Hello, we´re having problems during the restore of an Oracle database.
We backup the database with the hot_database_backup.sh. Everything is OK
till here.
When we want to restore it, we found this error:

RMAN-08523: restoring datafile 00001 to
/export/home/sistemas/oracle/system01.dbf
RMAN-08523: restoring datafile 00005 to
/export/home/sistemas/oracle/NBP_indices.dbf
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure during compilation of command
RMAN-03013: command type: restore
RMAN-03006: non-retryable error occurred during execution of command:
IRESTORE
RMAN-07004: unhandled exception during command execution on channel t1
RMAN-10035: exception raised in RPC: ORA-27192: skgfcls: sbtclose2 returned
error - failed to close file
ORA-19511: sbtclose2: Failed to process backup file.
ORA-19573: cannot obtain exclusive enqueue for datafile 4
RMAN-10031: ORA-19583 occurred during call to
DBMS_BACKUP_RESTORE.RESTOREBACKUPPIECE
Recovery Manager complete.

What can be happening??
Thanks in advanced!!