Forcefully termination

Dear Sir, i am working in one of private company, and company has terminated me because of some else's mistake and behaviour. one of employee has raise concern against HR manager and Location head to head office, as complain was against HR manager and location head, so he has not marked to them in that mail, Afterwards he forwarded that mail to me and i have not taken any action on that mail but directly i have deleted that mail. Now HR manager and location head claiming that, as he has forwarded that mail to me so you also have to leave the company, and asking my resignation. i told them what is my fault if he has forwarded that mail to me, but they are not listening me. When i went to office next day they wrote 'resigned' against my employee number and name, where i have not resigned and my all access deactivated. I tried to speak to them various way but they are not listening me , then i have decided to to complaint for it, but no one is listening me. Kindly suggest what should i do.. Thanks, Prashad.M