New ARRIS G34 works with phones and iPads, but TVs and PS5 have no Internet

I bought an ARRIS SURFboard G34 today and activated it with Xfinity. It has a solid blue light.

Our iPads and iPhone have Internet through its Wi-Fi. I confirmed the iPhone works with cellular data turned off. However, our TVs and PS5 connect to the network but cannot access the Internet.

The PS5 normally connects directly to the G34 with an Ethernet cable. It successfully obtains an IP address, but the Internet connection test fails. I also tried connecting it over Wi-Fi, with the same result.

So far, I have tried:

Restarting the modem and devices.

Setting the PS5’s IP and DNS settings to Automatic.

Trying Google DNS.

Temporarily lowering the G34’s firewall setting, then putting it back when that didn’t help.

The G34 shows its Internet connection as active and registration as complete. Its built-in IPv4 test reports “Error” for both 8.8.8.8 and 1.1.1.1.

Our old Motorola MG7550 is unplugged. The PS5 is the only device connected to the G34’s Ethernet ports.

Xfinity support said everything looks good because the iPads work, but the TVs and PS5 still have no Internet.

Can someone help check whether my new modem is set up correctly with Xfinity, including its IPv4 connection? I’m not sure whether this is an Xfinity issue or an ARRIS issue.