I did not receive report subscribed via report subscription. What could be the reason?

I did not receive report subscribed via report subscription. What could be the reason?

If a particular KPI or a list of KPIs are selected as part of the report subscription then, if any of these KPIs have undergone a change w.r.t its original KPI configuration (for e.g., either a measure used in the KPI is modified/delete) then, the individual KPI will work as expected but since the KPI used as part of the report subscription is undergone a change w.r.t its configuration, the report subscription will not work. If these subscriptions are deleted and re-created, the 'Report Subscription Mgmt.' will work as expected.