Xcp-ng, pfSense & OVH

I am trying to get pfSense working as a VM on xcp-ng with OVH however I am having trouble configuring the WAN interface in the pfSense setup.

I have added a vrack in OVH for the internal LAN. (10.44.50.100)

I have configured an additional IP with OVH and allocated an OVH MAC to it

I have the xcp-ng configured using the OVH public IP and this works as I can access XO Lite

I have created a pfsense VM and assigned the additional IP’s MAC address to VIF#0

When configuring the WAN interface in pfSense I have assigned the additional IP value however keep getting an error on the GW value.
“Cannot set WAN interface Default Gateway: 100.64.0.1”

I am using the GW value assigned by OVH for the host.

In pfSense, the default gateway needs to be in the same subnet range as the WAN IP.