GLOBAL_NAMES Domain is not going away (forcing a change)

I didn't found solution so I fixed in this way:

db_domain is null

a domain is added and can't be set to null

select * from global_name;
ABVP.WORLD The domain always stays

alter database RENAME global_name TO XXX; xxx.world

Changing domain the domain stays again
alter database RENAME global_name TO XXX.com.bo;

select * from global_name;
XXX.com.bo

alter database RENAME global_name TO abvp;  select * from global_name;
abvp.com.bo

Chaging directly in the sys table, and rexecuting change to get a correct change in the database dictionary:

UPDATE SYS.props$ SET value$='ABVP' WHERE name='GLOBAL_DB_NAME'; COMMIT;
  select * from global_name; --ABVP
alter database RENAME global_name TO XXX;   select * from global_name; --XXX
alter database RENAME global_name TO ABVP;   select * from global_name; --ABVP

Thank you :)

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