@Kathy_Z - Updating the driver didn't make any difference. Turning off the Wi-Fi reduced the frequency of losing connection, but it is still occasionally lost. However, the speed is extremely slow, less than 15 Mbps, when it's 130+ Mbps when using Wi-Fi. The ethernet is running at 1 Gbps, and other computers connected via ethernet are seeing speed around 150 Mbps.

@Kathy_Z 

System info:

Dell Inspiron 15 7591 2-in-1

Internet speed test varied, usually 120 Mbps to 140 Mbps (which is the expected speed), occasionally less than 20 Mbps due to some issue.

I posted a question at Amazon, and at least one other person is having the same problem:

I have problem with loosing connection.

Ethernet card is disappering for a while in device manager so Internet is loosing on this time:

I have same version V1.

Windows 10 PRO 2004.

Laptop Dell Vostro 3560.

When same cable is connected to ethernet in laptop or in another USB Ethernet adapter Gembrird everything is ok.

Spped of connection is same on all ethernet cards.

It happens every 5 minutes...