@bodi1 

Thank you for posting on the TP-Link Community.

Can you please kindly verify what is the system version of the Windows computer, is it Windows 10? What is the driver version for this T4U adapter, please check it as this:

https://www.tp-link.com/support/faq/2722/

When the computer is restarted every time, and you tried to connect to the 5G network, was there any error message? Does it connect to the 2.4G network automatically after startup? I found a similar feedback on Microsoft site, please kindly have a reference: https://answers.microsoft.com/en-us/windows/forum/windows_10-networking-winpc/windows-10-wifi-doesnt-auto-connect-to-wifi/05e1e28b-8028-44b3-a98b-51b2e64ab2fb

It is also suggested to modify the 5G wireless settings on the router, such as changing the wireless channel and channel width, you may run a Wi-Fi analyzer to verify which are the clearest channels, choose that one; change the channel width to 40MHz, then reboot both the router and computer to give a shot.