refresh materialized view ORA-01031: insufficient privilege

Hi , Can anybody help me which privilegies i need : I have two schemas TEST1 , TEST2

in TEST1 i have materialialized view and I have privilege

Grant select on MW to TEST2

But from test 2 :

BEGIN dbms_snapshot.refresh('TEST1.MW', 'C',NESTED => true); END;

ERROR at line 1:

ORA-01031: insufficient privileges

BEGIN dbms_snapshot.refresh('TEST1.MW', 'C',NESTED => false); END;

ERROR at line 1:

ORA-23401: materialized view "O_DL_STARBYTE"."PKS" does not exist

Do you have idea how to solve it ?

Database version is 12.1.0.2  ... I didn't find solution or bug in metalink

thank You B.