Could you let us know who your internet service provider is and the internet speed plan you are subscribed to?

Would it be possible for you to connect a computer directly to the gateway using an Ethernet cable? This would help us determine if the internet drops only on the Wi-Fi, or if it affects both Wi-Fi and hardwired connections.

Make sure that the gateway is placed in an open area to minimize Wi-Fi congestion.

If you find that the internet drops only on the Wi-Fi, I would suggest trying to change the Wi-Fi channels to improve the connection

It would be helpful to try changing the Wi-Fi channels to reduce congestion and improve the connection quality.

Please refer the link below, where you can find the steps to change the Wi-Fi channels 

http://arris.force.com/consumers/articles/General_FAQs/G34-G36-Changing-the-Wi-Fi-Channel

Xfinity - 300 Mbps

I don’t have any device that connects via Ethernet.

last time xfinity came they did the channel change process. I had no issues for 26 days. Wondering if this happens when there is some sort of update????

I understand that the intermittent issue has persisted for 26 days. I recommend changing the Wi-Fi channels using a spectrum analyzer.

WiFi congestion or heavy traffic may be causing the issue to recur. A spectrum analyzer can help identify the least congested channel, which may improve performance.

Additionally, ensure that the modem is placed in an open area to minimize interference. Please refer to the link below for step-by-step instructions on changing the Wi-Fi channels.

http://arris.force.com/consumers/articles/General_FAQs/G34-G36-Changing-the-Wi-Fi-Channel