Some of my devices are unable to look up Orbi

I’ve recently purchased the RBK40, and after setting it up on the orbi app. I’ve noticed that a few of my devices are unable to look up my wifi ssid. I’ve tried renaming it, turning the guest wifi on and off , rebooting it a few times, but nothing nothing works. These devices include the original PS4(not Pro nor Slim), an old laptop. I’ve realized that these devices only run on 2.4Ghz for the signal. Sorry I have little understanding on wifi technology, what do I need to do to get my WiFi being discovered my older devices?