MTNL Delhi — it was unable to increase my internet speed..

R/s, Sir my telephone no.22185589 registered name Vimla. Sir my problem is that my internet speed is very low. Sir my plan is 795 in this plan mtnl give me 2Mbps speed in 10gb when 10gb is finished my internet speed is at 512 kbps but i will not consume whole 10gb bundle so why my speed of internet and wifi is very low. i also complaint in mtnl complint no. 1504 and i email at mtnl helpdesk, talk to jto and sdo but no one response me. Sir i am a student internet is really important for me i study iit-jee so whenever i watch lectures with low speed of internet i can't watch it and when i use wifi in my smartphone the 32mb file will download in 25-30 minutes. So, please i humble request you to sir please increase my internet speed as fast as you can...sir please do something because mtnl not provide such type of speed that i wish. So, Sir please you could do something or take action on them..