Hello, friend!
According to your problem description, I suspect that the gateway address conflict may occur. As a result, the device is connected to the router but fails to obtain the correct IP address. Alternatively, multiple DHCP servers exist on the LAN and packets are not forwarded to the optical modem.
Please confirm the following information:
1. Detailed networking topology, Internet access mode of each route, and gateway address of the router;
2. Check whether the primary route connecting the device to the AX3 pro can access the Internet.
3. Change the primary route of the AX3 pro to the bridging mode, and reconnect the device to check whether the device can obtain the correct IP address and access the Internet.