[SOLVED] Can't port forward and router is getting the wrong public IP

[name100001]

I can't seem to port froward anything, I know my settings should be correct because I have not changed anything and they used to work.
When trying to work out whats wrong, I noticed the public IP address shown on the router (Fritz box 7490) was different from the IP address shown on canyouseeme.org.
I'm thinking these two things might be related since they started at the same time.
Does anyone know whats wrong and how to fix it?

 

[kanewolf]

What is the FIRST number that the router thinks is the WAN IP address?

 

[name100001]

What is the FIRST number that the router thinks is the WAN IP address?

100.66.xxx.xxx
Its in the Carrier-grade NAT range

 

[bill001g]

You have identified your own problem then.

The ISP is doing NAT on one of there routers. You would have to put in port forwarding rules there which is impossible.

Your only possible solution is if you ISP offers public IP. They may want to charge extra but many do not have the ability. Carrier NAT is extremely common in mobile broadband installs