While pairing your grill to your phone, you may see receive a message saying, "Grill Couldn't Find Network," or, "Grill couldn’t find the network. Please check that the network is using the 2.4GHz band and the signal is strong enough to reach the grill."
There are three possible scenarios for receiving this error.
Try to pair your grill without using a QR code
Run a speed test to ensure you have a strong enough signal. You can run a speed test by downloading a free speed test app from an app store. Make sure when running the test that you are in the same location your grill will be.
If the speed test comes back strong, power cycle the grill (turn off, unplug and turn on again), and attempt to re-pair your grill and app. Using the manual connection process rather than using the QR code may be a better option, especially if you have ever replaced your controller.
If the device is still connected to the grill WiFi, forget that WiFi network within your phone's WiFi settings. The device thinks that the grill SSID is stronger than the actual WiFi network.
Optional: Restart router.