Auth_topeer_failed

Installing and Using OpenWrt Network and Wireless Configuration
1

Hey guys, I change my ISP and try to connect my router again using PPPoE, but I'm getting the PPP message Unknown error (AUTH_TOPEER_FAILED).

I access the ISP router to check credentials and they are the same, without @isp sufix:
User: scoth
Pwd: 0123

I can't find much info about AUTH_TOPEER_FAILED, but seems like user/password is incorrect.
Is there any other configuration that can get to this error ? Firewall, ISP Block ?
I'm using a Fiber connection.

In PPPD git file auth.c there is a comment:

/*
 * We've failed to authenticate ourselves to our peer.
 * Some servers keep sending CHAP challenges, but there
 * is no point in persisting without any way to get updated
 * authentication secrets.
 */

Can, anyone explain what this mean, CHAP challenges ? Could be it ?

2

Get it fixed. After make a macaddr clone it works. ISP probably allowing only its own hardware to connect.
Now internet is up and running only with OpenWRT again!