Deducted the whole salary and not providing relieving letter

Hi, I left the company for which i was working by serving a very short notice period. I had resigned on 23-OCT-2015 and left the company on 26-OCT-2015. I requested them to adjust my pending leaves with the notice period, they didnt do that, i asked them to deduct my basic salary to provide relieving letter they didnt do that, i asked them complete exit formalities they didnt do that. I left that company and i joined a new company. The company had 18 to 18 payroll cycle. I had joined the company on 8-12-2014 and in the first month i had received only 10 days salary as per their payroll cycle. When i left the company on 26-OCT-2015, as per their payroll cycle i had worked for 12+26 = 38 days. Plus i had 8 pending leaves. They did full and final after almost 2.5 months and just gave 13000 as fnf amount. My salary was 29000 gross and used to get 25200 net every month. When i left the company they put my salary on hold. And when i contacted them the hr personnel said as i didnt serve the notice period they deducted 26days salary. Asked why you guys did that, stated that its our company's policy. I said if you deducted my 1 whole months salary along with the dues then provide me my relieving letter. Said you didnt serve the notice period so you wont be getting that so i asked why did you deduct my salary then? Said its written in the offer letter if somebody doesnt serve the notice period we recover the amount from the salary. Told him if i didnt serve the notice period, you have every right to not provide the salary for the days i didnt come for work but i should get salary for the days i worked. Said no we deduct the salary for the days you didnt serve notice period from your salary. What should i do? They are neither giving the salary which they deducted wrongfully nor the relieving letter.