Error in fillReport

We've been seeing certain scheduled reports fail at random times for the same reason with no luck in finding a solution. When we see a report fail, we have to go in and Fill Report in Background and they complete fine. We get the same error every time:

Error in fillReport

com.aveksa.server.runtime.ServerException: net.sf.jasperreports.engine.JRException: java.sql.SQLException: ORA-00942: table or view does not exist

    at com.aveksa.server.report.Report.fillReport(Report.java:1688)
    at com.aveksa.server.report.Report.fillReport(Report.java:1665)
    at com.aveksa.server.report.ReportRunnerTask.process(ReportRunnerTask.java:119)
    at com.aveksa.server.scheduler.ScheduledTask$Executor.execute(ScheduledTask.java:159)
    at com.aveksa.common.ThreadPool$Executor.run(ThreadPool.java:141)
    at java.lang.Thread.run(Thread.java:745)

If the table didn't exist then the query should never work.

example query:

(select unique
  'Account' as collector_type,
  ac.RUN_ID,
  ac.NAME,
  ac.START_TIME,
  ac.STATUS
 from avuser.PV_ACCOUNT_COLLECTION ac
  where trunc(ac.START_TIME) = trunc(sysdate)-1

 
 union
 
  select unique
  'Identity' as collector_type,
  pc.RUN_ID,
  pc.NAME,
  pc.START_TIME,
  pc.STATUS
 from avuser.PV_IDENTITY_COLLECTION pc
  where trunc(pc.START_TIME) = trunc(sysdate)-1
  union
 
  select unique
  'Entitlement' as collector_type,
  ec.RUN_ID,
  ec.NAME,
  ec.START_TIME,
  ec.STATUS
 from avuser.PV_ENTITLEMENT_COLLECTION ec
  where trunc(ec.START_TIME) = trunc(sysdate)-1
 
  union
 
  select unique
  'Multi-App' as collector_type,
  mac.RUN_ID,
  mac.NAME,
  mac.START_TIME,
  mac.STATUS
  from AVUSER.PV_MULTI_APP_COLLECTION mac
  where trunc(mac.START_TIME) = trunc(sysdate)-1
  ORDER by START_TIME desc)