when i ran My Bi reports I'm getting error is ORA-01427: single-row subquery returns more than one

Summary:

Hi Team,

when i run my report some countries coming data and some of times als coming the data but some times I'm getting below errror:

ORA-01427: single-row subquery returns more than one row

even schedule the job also same error coming

even i put the condtion : and ROWNUM <=1 then some times working but now not working.

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