WAN connection issue with 3rd party router

[thelarch77]

Hi, I have an ASUS AX86U router that has been successfully connected to my ONT for nearly 2 years and has worked well. This morning, after a routine weekly auto reboot of the router at 3am (these have been scheduled weekly since setup), the router fails to renew the lease on the WAN IP. It appears to get an IP then after 10 seconds or so switches back to 0.0.0.0, the router UI shows the lease has expired and it's trying to renew.

The logs show that authentication has been successful but after there are the 2 messages saying 'connection terminated' and 'modem hangup' and then the loop starts again.

To get network back I have had to put my EE Hub in (the first time it's been powered on and connected, ever!) and am using it to feed my ASUS network.

I don't like having a double hop to get to the outside world or having to power another device, so does anyone have any thoughts as to what could be causing the issue?

Thanks in advance 

[Mustrum]

@thelarch77  I know what you mean, it can be frustrating when things work again with no explanation.

On other sites where they have helpful staff members supporting customers, sometimes the PPOE session can get stuck - known as a stale session. The server thinks all is well, but the router cannot connect. 

Did you speak to any "helpful" EE tech staff members?

I also notice you have Dual WAN on, if you don't mind me asking, what do you have on the other WAN port? I am in need of a new router, tried my DSL 82 on a 1Gb connection, but throughput is too slow, DSL side is fine, just researching options at the moment. 

[thelarch77]

@Mustrum the other WAN is just a Huawei 4G USB stick and Dual WAN is setup to failover, which I finally got round to plugging in and configuring last week when I was facing the issues.