Port forwarding issue HUB 5

Greetings to the esteemed community,

I seek your expertise regarding a technical matter concerning port forwarding on the HUB 5 device. Within my local area network (LAN), I possess multiple "smart devices" that can be accessed and controlled locally through a web browser interface by inputting their respective IP addresses, such as 192.168.0.10, 192.168.0.11, and so on. These devices utilize local port 80 (HTTP) for communication.

However, I am facing a challenge in configuring these devices to be accessible from external locations.
While I have successfully established port forwarding for only one device with the configuration
WAN IP - 86.xxx.xxx.73:190 -> Port forward to -> 192.168.0.10:80,
Subsequent attempts to set up additional rules encounter a conflict within the router due to port 80 being already in use. example WAN IP - 86.xxx.xxx.73:191 -> Port forward to -> 192.168.0.11:80,

I kindly request your assistance in understanding this issue and providing a simplified explanation of the underlying technical concepts. Your expertise in this matter would be greatly appreciated.

Thank you for your attention to this inquiry experts 😉