Not releaving the from the company

I worked for a private company for 9 months. as per appointment order first 6 months will be probation period. After six months i didnt get any letter or any confirmation from the company. As per the appointment order terms till confirmation i will be treated as probation period employee only. I declare my resignation on 28th may. but they didnt accept and they asked me to continue with the job. But suddenly without any notice they hold my may month salary. Also i worked till june 15 th. so totally they hold my 45 days salary. Now i given for my resignation letter again they are threatening me to work for next 90days or give us 90days salary. Then i applied for 2 months leave. now what i have to do. Is there anypossibility that company will take legal action on me. i want to releave the company immediately. As per appointment order notice period for probation period is 30 days. they hold my 45days salary. I also handed over all the company details sim and laptops to the company.Kindly help me to procee. As of now i am on leave for 2 months. how can proceed further.