If local viewing works but the internet path does not, the device and internal network are fine. Focus on the WAN edge.

1. Cloud registration status: first confirm the device shows as online on the cloud platform. With P2P, successful registration to the service is normally all that is needed, with no public IP required.
2. NAT and port forwarding: when forwarding ports, verify the router rule is active, internal and external ports match, and the ISP has not blocked common ports such as 80 and 8080.
3. Carrier-grade NAT: many consumer and business lines are behind operator NAT with no true public IP. Port forwarding cannot work there; use P2P or a VPN instead.
4. Upstream bandwidth: pulling the main stream remotely demands substantial upload capacity. Default remote viewing to the sub stream and switch to the main stream on demand.

On corporate networks, also check the egress firewall. Many organisations block inbound access to internal ports by default, so an IT policy change is required.