Unable to Activate Standby log (OGG)

Hi Experts,

we have a standby log issue on our downstream DB ,the standby log can't be activated, ,which cause our OGG can't work in a real time apply mode

SQL> SELECT GROUP#,THREAD#,SEQUENCE#,ARCHIVED,STATUS FROM V$STANDBY_LOG;

GROUP# THREAD# SEQUENCE# ARC STATUS

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

6 1 0 YES UNASSIGNED

7 1 0 YES UNASSIGNED

8 1 0 YES UNASSIGNED

9 1 0 YES UNASSIGNED

10 1 0 YES UNASSIGNED

11 2 0 YES UNASSIGNED

12 2 0 YES UNASSIGNED

13 2 0 YES UNASSIGNED

14 2 0 YES UNASSIGNED

15 2 0 YES UNASSIGNED

10 rows selected.

Need help to resolve the issue.

Regards

Vivek