Hi, friend!
If the Wi-Fi names for 2.4 GHz and 5 GHz are the same by default, you will automatically connect to a faster Wi-Fi network.
If you only want to use 5 GHz Wi-Fi, you can disable the Priority 2.4 GHz feature by performing the following steps:
1) Connect your phone to the router's Wi-Fi network.
2) Enter 192.168.3.1 in your browser address bar and follow the onscreen instructions to log in.
3) Select My Wi-Fi and disable Prioritize 2.4 GHz.
You will now be able to find two Wi-Fi network names. Connect to the Wi-Fi network with "_5G" at the end of its name.
Thanks!