Object doesn't exist

[malru]

Hi,

When I'm trying to create a materialized view,it's saying

ORA-00955: name is already used by an existing object

But actually this object is not existing in my schema and i verified it by,

> select object_name,object_type from user_objects where object_name='MV_STEPUP';
no rows selected

and

>drop materialized view MV_STEPUP;
ORA-12003: materialized view "DMUSER"."MV_STEPUP" does not exist

Please someone help me to resolve this issue,so that I create this object.

Thanks..