CTS wrost experience

Hi everyone, I have joined CTS recently,after joining into the project I have been mentally harassed by the senior officials and black mailed to complete the entire project alone. They themselves put me into the bench without requesting for it and threatening that they will make sure I clueing HR will not allow to move to different and ultimately to terminate from the job. I have resigned as it's been amental pressure and even after that they have moved me again to he same project from bench and asking for o complete the entire project till LWD. I still agreed to it and working on the project. One day HR called me and said that they will prepone my LWD and I agreed to it and moved out of the company. It's been 4 working day and they haven't given me the relieving and resignation acceptance letter. I have been in touch with them via emails but no response. Kindly let me know how to project on this as I'm not able to join the other company without the exit documents.