First, I would verify that the latest version of the Tableau WDC is in use, by leveraging the WDC SDK found at the following GitHub site. https://github.com/tableau/webdataconnector
Additionally, I would add yourself to the following issue on the Tableau GitHub page, as it seems that you may not be the only experiencing the issue.
I have also moved the post to the Tableau Community section specified for the WDC.
I hope this helps!