Failed to get test Metric Extension metric result.: no out-bind bound

Hi,

I am using PL/SQL in metric extension and getting error:

Failed to get test Metric Extension metric result.: no out-bind bound

Below is plsql:

declare gap integer;

begin

IF not dbms_utility.is_cluster_database THEN

     select sum(local.sequence#-target.sequence#) Total_gap into gap

    from (select thread#,max(sequence#) sequence# from gv$archived_log

where standby_dest='YES'  and applied='YES'

and first_time between sysdate-7 and sysdate

group by thread#) target,

(select thread#,max(sequence#) sequence# from gv$log group by thread#) local

where target.thread#=local.thread#;

end if;

end ;

I have defined out parameter position 1 and out parameter type as SQL_CURSOR