Drop attempt

Input

./rcu -silent -dropRepository -schemaPrefix DEV -connectString test-db1:1521:RCUDEV -dbUser sys -dbRole sysdba -component STB -component IAU_APPEND -component OPSS -component BIPLATFORM -component IAU -component MDS -component IAU_VIEWER -component WLS

Output

Processing command line ....
Repository Creation Utility - Checking Prerequisites
Checking Global Prerequisites
Repository Creation Utility - Checking Prerequisites
Checking Component Prerequisites
Repository Creation Utility - Drop
Repository Drop in progress.
Percent Complete: 2
Percent Complete: 12
ORA-38881: Cannot drop tablespace DEV_IAU on primary database due to guaranteed restore points.
...
...
...

Investigate via SQL

SELECT NAME FROM V$RESTORE_POINT;

In my case it returned FRESH_DB. I must have created a snapshot a while back of a clean database to quick restores during my development testing.

Drop it

drop restore point FRESH_DB;

Restore POINT dropped.