Does not possible to use - in usernames, because CLI script replace it to _
[email protected]# run show configuration commands | match local-users set service pppoe-server authentication local-users username [email protected] password 'test' [edit] [email protected]# sudo cat /run/accel-pppd/pppoe.chap-secrets # username server password acceptable local IP addresses shaper [email protected]_example.com * test *