virtual Sophos UTM PPPOE problem

Hello guys,

I deployed a Sophos UTM in my ESXi environment and i cannot connect with it to my ISP using PPPOE. Although i made a normal PPPOE config and also the credentials are OK (tested on a TPLINK and directly on my PC - working just fine), i am not able to succesfully establish a connection.

Here is the config of the interface:

And here is what the log shows:

So i started to dig it up, but i could not find a solution to my problem. However, i found this guys's thread: https://community.sophos.com/products/unified-threat-management/f/management-networking-logging-and-reporting/34822/solved-unable-to-authenticate-with-pppoe

I tried his way by adding blackslash \ at the beginning and at the end of the username, like in the picture bellow:

Log output:

As you can see, logs are different, but still not working.

I have another Sophos (but physicall) with the same kind PPPOE setup from the same ISP and that one is working just fine. I have no ideea why the authentication fails on the virtual Sophos. I have no ideeas left. 

Please assist.

Thx