upgrade from 11g to 19c

Hi,
I've upgraded a UAT instance from 11g to 19c. in this database there was replication

SQL> select distinct gname from dba_repobject;

GNAME

------------------------------

REP_MG

SQL>

After the upgrade, this GNAME is not there anymore. and I get this error message:

SQL Error: ORA-23474: definition of "OWNER"."TABLE" has changed since generation of replication support
ORA-00942: table or view does not exist

https://docs.oracle.com/error-help/db/ora-23474/23474. 0000 - "definition of "%s"."%s" has changed since generation of replication support"
*Cause: The current columns in the specified table and their column types
do not match the columns and column types when replication support