Hi gaggz even i had same problem but with broadband lan connection. It says already logged in and cust care couldn't do anything instead he eat my head and i was so much frustrated explaining him of sessions thing.NO USE. Does Reliance have some real technical guys BIG QUESTION??? Downloads breaks...
To this already logged in thing I tried something which worked you can try but not sure if it works .
Try putting username only hit enter,it gives error invalid usrnam , then try putting wrong username and wrong password, repeat this many times as many 5 to 7 times then put Correct username and Password and it worked for me.No need to wait for 6 hrs for this bull shit technical BUG .

Other thing you can try is on commpand prompt type command:
ipconfig /release

This release ip address then u shut off modem and computer and restart it after some time. or do things which terminate session like leaving machine not doing any internet activity and keeping it idle for some time. Hope something works.
Else im in process of finding a core solution to this problem.