Trending @Capgemini; Should I work on Bench and on notice period

As I had resigned due to bad politics in my project without any offer letter and now only one month is left in my notice period. Even in notice period, they harassed me mentally by giving unrelevant work load and I wanted to say NO but I was afraid about experience letter but now have put me on bench so can I say NO now as I am not the part of project? I want to work but not for these guys. Please suggest.