Drilldowns may be unavailable throughout the day in intervals of about 15-20 minutes.
A reason why drilldowns may be unavailable throughout the day could be do to the tenant's OLAP reporting being powered by Scalable Cost History. Scalable Cost History is a data processing method where Cost and Usage Reports (CUR) are updated multiple times day by AWS. When CUR's are updated, drilldowns will be unavailable for about 10-15 minutes.
If drilldowns are unavailable for longer than 30 minutes, please open a case with Support.