It sounds like your router may be behind a CGNAT. Could you please confirm if the router itself gets the public WAN IP assigned or does the WAN interface have any IP address from the following list:
10.0.0.1 - 10.255.255.254
100.64.0.1 - 100.127.255.254
172.16.0.1 - 172.31.255.254
192.168.0.1 - 192.168.255.254
Please note that WAN IP and the displayed IP address from "curl ifconfig.me" may differ, checking the WAN interface IP is the best way to approach this issue.
If you have any of these addresses on your WAN interface then I'm afraid it's going to be impossible to access your router remotely without some workaround.
If this turns out to be the case, for the workarounds, the best and simplest way would be to request for a public static IP address from your ISP. There is another way - it's possible to rent a virtual private server (VPS) with an external IP address, configure a VPN tunnel between the VPS and the router and port forward certain ports via the tunnel but this method is much more complicated and requires some manual setup.