Power BI Dataflows failed to refresh when computed entity is created

I have dataflow created with entities pulled from CRM and Trello. 

Then I created some calculated entites by merging two or more entities.

Then I scheduled refresh for this dataflow and it was refreshing fine.

Everything was working fine till May 13th, 2019 after that dataflow stopped refreshing with the below error message for calculated entities:

Error: An internal error occurred... RootActivityId = 1d3ecb4f-35db-4257-87bd-ae9104a1b155.Param1 = DataflowInternalError Request ID: f1588455-7a9e-49af-6b4f-c8837315d4fc.

Any help on the above scenario? why dataflow is not refreshing with calculated entity.