Delete database Using dbca using slient command

[oracle@OEL76 bin]$ /oracle/product/12.1.0.2/dbhome_1/bin/dbca -silent -deleteDatabase -sourceDB orcl12c -sysDBAUserName sys -sysDBAPassword system123
Connecting to database
4% complete
9% complete
14% complete
19% complete
23% complete
28% complete
47% complete
Updating network configuration files
52% complete
Deleting instance and datafiles
76% complete
100% complete
Look at the log file "/oracle/cfgtoollogs/dbca/orcl12c1.log" for further details.
[oracle@OEL76 bin]$
[oracle@OEL76 bin]$
[oracle@OEL76 bin]$ more "/oracle/cfgtoollogs/dbca/orcl12c1.log"
The Database Configuration Assistant will delete the Oracle instance and datafiles for your database. All information in the database will be destroyed. Do you want to
proceed?
Connecting to database
DBCA_PROGRESS : 4%
DBCA_PROGRESS : 9%
DBCA_PROGRESS : 14%
DBCA_PROGRESS : 19%
DBCA_PROGRESS : 23%
DBCA_PROGRESS : 28%
ORA-01078: failure in processing system parameters

DBCA_PROGRESS : 47%
Updating network configuration files
DBCA_PROGRESS : 52%
Deleting instance and datafiles
DBCA_PROGRESS : 76%
DBCA_PROGRESS : 100%
Database deletion completed.
[oracle@OEL76 bin]$