DD-WRT configuration for ACT Fibernet

I have been using DD-WRT for years, but hadn't upgraded the firmware in years. I decided to do it yesterday and after that I am not able to connect using PPPOE. I am able to log in via https://selfcare.actcorp.in/web/blr/home when I set the connection type to Automatic Configuration - DHCP.

Settings: (screenshot attached)
Connection
Username: ACT username
Password: ACT password.
MTU 1492

Router Model: Buffalo WZR-HP-G300NH2
Firmware: DD-WRT v3.0-r41892 std (01/05/20)

I have not done a 30-30-30 reset yet. Is there something I am missing here?

looks fine for me do not no whats going on

I can't figure it out either. i tried 30/30/30 reset, reflashed. Finally I put a 2nd router before it for PPPOE, double NAT. I will have to buy a new AC router and then would probably keep the DD-WRT for VPN. That way I can have 1 AP without VPN and another with VPN.

What does the PPP authentication log show? Could you pls post the log?

When I was setting up a new router a while ago, I was able to conenct via PPP only after logging out of the ACT portal using DHCP. So if you are logged in via DHCP and then switch to PPPoE on the router, it won't connect unless you log out of the DHCP thingy. Something worth trying.

@1morsj If you haven't yet found a solution. Try reducing the MTU value to 1460 or lower.