Failover not working

[spitfire852]

I have been trying to setup a new install of opnsense with the latest build and having major issues with getting failover WAN to work. I have followed the documentation a few times and a couple of older videos around the topic but I can't for the life of me get it to work.
https://docs.opnsense.org/manual/how-tos/multiwan.html

I am able to see that the WAN2 interface is online and that it is pinging a monitoring ping location configured to 1.1.1.1. All seems to be in order until you unplug the primary WAN and nothing happens. It has to be something to do with the firewall rule or internal routing but I can't see anything that I have missed.

Has anyone got this up and running with out any issues on a new install rather than upgrade? I would love some help.

[tiermutter]

Up and running since some years without any issues
Please provide some screenshots:
- Gateways
- Gateway groups
- FW rules of related interfaces (eg LAN)
- Configured DNS server at system/settings/general

Please also explain what is meant with 'and nothing happens.'
Is internet access still possible? Is the gateway tagged 'down'?
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