Deployment pipeline error - not bound

This happened to me. I created a folder in my "Dev" workspace to move my report to that folder. When I tried to deploy that report from "Dev" to "Test" workspace, I encountered the same error message "Deployed items with the same name in the target and source stages are not bound. This may be due to recent actions, such as deleting or adding new items, still being in process.". 

After 2 days of struggle, I solved the issue by simply moving the report out of the folder in the "Test" workspace, then continued with the normal deployment procedures. I'm not sure about the technical aspect behind the scenes, but I hope it helps.