Need Carrer advice

I am currently stuck in an IT company where they falsified my work experience without my consent just to place me with a client. Now, they are blackmailing me by threatening to give me a bad reference and withholding my relieving documents if I try to leave. What are my rights in this situation, and how can I safely exit this toxic environment while protecting my career and reputation? Has anyone faced similar employer blackmail or unauthorized falsification of employee records, and how did you handle it?