PPPOE won't establish when previously worked on a Cisco 887

I can't get PPPOE to establish it just sticks at initialising when going between a 40F and a Virgin Small Business Hub (UK ISP).

It works fine with Cisco (config below) but won't come up with my FortiGate. One thing I've seen is that the Cisco was set specifically to CHAP. So I'll try that next time but wondering if anyone has had any first experience with this issue?

Relevant Cisco Config (identifying info. scrubbed):

interface FastEthernet3  description Virgin Media cable circuit ref: REFERENCE  no ip address ! interface Virtual-PPP1  description Virgin Media circuit ref: REFERENCE  bandwidth 3084  ip address negotiated  ip idle-group 1 in  ip idle-group 1 out  ip mtu 1460  ip tcp adjust-mss 1420  load-interval 30  no cdp enable  keepalive 3  ppp chap hostname HOSTNAME@PROVIDER  ppp chap password PASSWORD  pseudowire 1.2.3.4 10 encapsulation l2tpv2 pw-class pwclass1 !

Relevant FortiGate Config (identifying info. scrubbed):

config system interface  edit "wan"   set vdom "root"   set allowaccess ping https ssh fgfm   set type physical   set lldp-reception enable   set snmp-index 1   set mtu-override enable   set mtu 1460  next  edit "ul-mpls-1"   set vdom "root"   set mode pppoe   set distance 10   set priority 50   set allowaccess ping https ssh http fgfm   set type tunnel   set tcp-mss 1420   set description "Virgin Media circuit ref: REFERENCE"   set role wan   set snmp-index 110   set interface "wan"  next end ! config system pppoe-interface  edit "ul-mpls-1"   set device "wan"   set username "HOSTNAME@PROVIDER"   set password ENC PASSWORD  next end