[oarsinsync]

> One is carrier grade NAT (CGNAT), which is used by ISPs that have run out of IPv4 addresses so you don’t get a real public IPv4 address, although you should have a public IPv6. If you’re unlucky enough to be on one of thee ISPs there’s likely not much you can do.

This is true. Your options look like:

1. Get a new ISP

2. Get a VPN that supplies you with a public IP (these exist)

3. Hope you can do whatever you need on IPv6 instead

[tomatocracy]

Some CGNAT ISPs will also sell service with a public IPv4 for a premium. That's probably the most "user-friendly" option but it's also probably something they don't advertise and you need to ask for explicitly, if offered.