Forcing to resign from company because they can't pay me salary

I work in facility manpower services company were my Manager & Assistant manager are forcing me to resign from my designation. And reason they have given me that other employees are working in less salary then why should we pay you more salary. They have not given me any mail also regarding this, but they daily ask me to resign. Actually they have some other reason to terminate me, I am pregnant and they never give maternity benefits to any employee. I am eligible for it.
In past also they did same thing with other employees also.
Please assist me in this case.

you are eligible for maternity benefit if you are confirmed employee. Do not give resignation and approach local labour officer. Make written complaint so they can help you to get your resignation. or discussed with them that you will give resignation but if they give you the notice pay salary as well as salary for 6 months against maternity benefit.
And if they say NO then go legally with help of local labour inspector. And if they say Yes then properly draft resignation letter and also mention that since company want my resignation hence I am resigning with immediate effect. and also mention the entire story of discussion where they promised you to may notice pay and maternity benefit etc.
Thanks & Regards,
Supriya P

Thanks for your reply,
I am not resigning from my post now, I am putting mail of Maternity leave lets she what they will do after that.One more thing now they are giving new reason of my performance. In 10 months now they are giving me silly reason.