@ JB701 , you were right . Hathways PPPOE setup specifically uses "HATHWAY" service name. I tried tweaking this and by trial and error I was able to confirm that if this service name is incorrect , for example even if it is spelled in small case like "hathway" then connection doesnt work (not even with existing 670L router). So now I think I have to find a router which has this service name field. I had 2 spare routers Tenda and D-Link , both of them doesnt have this field. Hence not sure how to add this service name field.