If you have a Pubit membership, log in to that, and remove the mss. from there. The Pubit side still works.
I have the exact same problem. I have sent 3 emails to them and have not heard back - at least they did acknowledge your email.
I realized the issue with my manuscript when I purchased the book and saw all of the previous versions of the manuscript in the table of contents section. I immediately took the book down, and have been unsuccessful in getting the problem rectified.