TS-464 - D-Link DWA 182 USB Adapter only connecting at 2.4 Ghz

I have a TS 464 NAS with a D-Link DWA 182 USB Adapter. It is connecting at 2.4 Ghz only. How can I force the nas to use 5.0 Ghz?

I take it your 2.4 and 5ghz wifi have the same SSID network name? how about creating a new SSID with just 5Ghz and see it it will join that SSID network?

Best course of action, if your QNAP HAS to be connected to wifi, is a wifi bridge. You connect to it via regular network it’s transparent to your QNAP.