Scheuled data refresh not working on two servers at same time

We are using PowerBI Report Server on premise and are attempting to use the scheduled data refresh.  We have two envionments, Test/Staging and Production which are on the same domain, but otherwise share no resources.

We setup our Test enviornmment and everything was workiing perfectly, including the scheduled data refresh.  Once we setup our production environment however, the scheduled data refresh on the Test environment ceased to function.  Thinking that we must have done something inadvertently to break it we attempted to troubleshoot and eventually rebuilt our Test system.  At this point the scheduled data refresh on the production environment ceased to function.

We rebuilt the Production environment and sure enough, as soon as we executed the first data refresh, the data refresh on the Test environment ceased to function.

This is too much of a coincidence.  These environments do not share any resources or Windows domain accounts although they are on the same domain and use the same DNS.  The failure message from the log is below:

Status: Error Failed Streaming model to Analysis Server, Exception System.AggregateException: One or more errors occurred. ---> System.AggregateException: One or more errors occurred. ---> System.ArgumentNullException: Value cannot be null.
Parameter name: s
at System.IO.StringReader..ctor(String s)
at System.Xml.Linq.XDocument.Parse(String text, LoadOptions options)
at Microsoft.ReportingServices.CatalogAccess.PolicyAcessor.<GetItemPolicies>d__3.MoveNext()
--- End of inner exception stack trace ---

Any thoughts?

Thanks,

John Bailey