Shri Ramswaroop Digital Technologies Private Limited - Not giving salary

My sister joined this company on **th September **** as an Associate Software Engineer. She is working with full efforts. But she is not getting paid. Till today, she has received only one month salary i.e. for October month. She is asking manager and Hr but she is getting excuses. They always tell that salary will be credited within few days but they never give. Other than that, if she resigns, she will have to serve ** days. For those ** days, they will give salary after her Full and Final Settlement. We are not getting any idea to whom we should complain. We are facing financial issues and I think other employees are also facing the same issue. Please help.