PPoE Wan connection drops over and over

Try updating the mss value from the console, login with the admin credentials via ssh > press 4 for the device console > and execute the following command: 
set network mtu-mss Port<no> mtu default mss <value>

Thanks What is ur suggestion for mss?

1452 or 1352 should be fine. Or you can also ask a recommended value from the ISP too to have proper negotiation.

is there any command from console enable ovverride mss ?

is there any command from console enable ovverride mss ?

Yes, this one >> set network mtu-mss Port<no> mtu default mss <value>
e.g. if the pppoe is configured on Port2 then cmd should be: set network mtu-mss Port2 mtu default mss 1352
It is also mentioned above !
And if works for you, please click on verify Answer.

thanks adjust mss command worked I am waiting for wan connection dropping problem 

wan connection is still drop around every 30 min one min down one min up do you have any idea?