pfsense dynamic dns (ddns) does not update to correct Public IP when it has a Local WAN address, but returns correct IP from rc.dyndns.update

[good4y0u]

I am trying to solve the problem that when pfsense is double-nat'd behind another router it cannot replace the ddns cache with the correct public IP, even though it can get the public IP from the http://checkip.dyndns.org update.

My pfsense WAN interface shows the local IP it is assigned. I intend this to be double-nat'd.

Under Services -> Dynamic DNS -> Dynamic DNS Clients
I see the following:

The status log shows: Which means it can actually see the correct public IP.

rc.dyndns.update: DynDns (vpn.DOMAIN.TLD): Dynamic Dns: cacheIP != wan_ip. Updating. Cached IP: 108.xx.xxx.xx WAN IP: 173.xx.xxx.xx

My pfsense is setup in a double-nat situation, it is behind an existing dhcp server and router.

I believe my issue is somewhat similar to what is described in this thread: [https://forum.netgate.com/topic/158230/custom-check-ip-service-not-working-there-was-an-error-trying-to-determine-the-public-ip-for-interface-wan?_=1637986251592](link url)

[Bob.Dig]

@good4y0u Your problem seems to be that you are not capable of setting up some private network in the first place.