EDIT: Still receiving these failed workflow emails.  Any Ideas?

SharePoint 2016 On Prem along with Nintex Workflow for SharePoint. We periodically backup our PROD WSS_Content Database (no Nintex databases included) and the restore down to our TEST environment. We are now experiencing "workflow failed to run" errors from the TEST environment of what appear to be the workflows running in PROD at the time we copied the PROD WSS_Content database. When I click on the link in the error email to view the workflow status, it points to our TEST environment and results in this message "Cannot find history for workflow with instanceId xxxxxxxxx-xxx-xxx-xxx. It may have been removed from the database." No workflows are running in the TEST system. Any thoughts on how I cancel those "phantom" workflows?