Why are my message store reports taking hours to complete?

RC Devs,

We're seeing an issue with message store reports taking many hours to complete.

The issue began on May 23rd/

This example took three hours:

{
"uri": "https://platform.ringcentral.com/restapi/v1.0/account/2480843036/message-store-report/2480843036-2609253036-a5a5b2d6c1fc46148e0cadfe74ee2a76",
"id": "2480843036-2609253036-a5a5b2d6c1fc46148e0cadfe74ee2a76",
"status": "Completed",
"startTime": "2020-05-27T10:06:02Z",
"finishTime": "2020-05-27T13:51:46Z",
"accountId": "2480843036",
"dateFrom": "2020-05-23T17:13:02Z",
"dateTo": "2020-05-27T10:06:02.369Z"
}

The data volume isn't that large. Message store reports prior to May 23rd were being generated in a few seconds.