How to unlock Airtel Xstream Router

[mythology]

Hi Guys,
I am trying to unlock router for changing PPPoE username and password but it doesn't allow me to access so can anyone please share how to fully access my router to make addition changes below are my router device information
Model Name
H660GM-A
Hardware Version
DPW-G-P-66GMAZ-A3
Software Version
V3.2.2120054
Manufacturer
DASAN Networks

Please let me know if you have any kind of information related to access superuser to unlock this router.

 

[nikola]

Looking for same for last 8 months, searched everywhere on internet, no luck.

 

[redhatperl]

No can do..

 

[nikola]

No can do..

Unless you are airtel network Engineer.