Hi @Netli,

Thank you for reporting your issue to our community.

May I know what troubleshooting have you done for Archer T3U nano? 

Here are some suggestions may help you:

Please refer to Case 2: What should I do if the TP-Link network adapter is not working properly in my computer? 
Step 1. Check Wi-Fi signal strength. If the signal is weak, move the computer closer to your router if possible.
Step2. Navigate to Device Manager in the Control Panel >> Locate the wireless adapter in the list.>>Highlight the device in the listing >> Right-click and Select Properties >> Power Management >>Uncheck Allow the computer to turn off this device.>> Click OK to close the window >> Reboot the computer.

Step 3. Check if the problem happens on 2.4GHz or 5GHz if it’s a dual-band adapter.
Step 4. Update the driver of the adapter (skip if you don’t know how to do that).
Step 5. Contact router support to change the channel and channel width on your router to avoid possible interference. 
Step 6. Please try to ping the router's IP address “192.168.0.1”(we take the TP-Link's router IP address as an example), then please share the ping result.

How to Use the Ping Command: How to use the Ping command | TP-Link

Please reply here with the results above and tell us the operating system of your computer and what it looks like when the connection drops as the Wi-Fi signal disappears or other behaviors.