I am trying to connect Connecting AC1300 Deco M5 to a BTOpenreach Modem. 
 

but the Deco M5 unit is not connecting to the internet. 
 

it detects that the modem uses PPPoe and asks for a username and password. 
 

I have looked this up on the BT forum and apparently the username is bthomehub@btbroadband.com and the password is BT. 

I have used these but when the setup app starts testing the internet connection, the light on the Deco unit turns red and the app says that the Username and password are wrong. 
 

what am I doing wrong? 
 

thanks.