Hi,
Our plugin was failing repeatedly with the below error message.
After some analysis we realized that it was because of using ExecuteMultipleRequest in the plugin and as we had multiple ExecuteMultipleRequest running at the same time. And as mentioned in the MSDN
https://msdn.microsoft.com/en-in/library/jj863631.aspx
We refactored the code to execute one request at a time and it fixed the issue.
Hope it helps..