C6250 Slow Upload Speeds

I'm directly connected to the modem on Windows 10, so no wifi testing being done here.

I'm currently paying Comcast for 100 down/5 up. Today, I've been having severe issues getting my upload above 1 Mbps when trying to stream content through Twitch TV. When I run speedtests on speedtest.net, I get about 4-5 upload going through Comcast's server. However, when I run it through Google Speedtest, I barely get 0.5 upload.

I contacted Comcast today to see if they were finding any issues on their end. They ran some diagnostics and find no issues on their end when they tried connecting to the modem. They suggested I contact Netgear for support on the issue.

I double-checked the modem settings based on previous posts, and everything looks fine as far as I can tell. However, I'm still having problems after several reboots and reconnections. Please advise. Thank you in advance.