Hello. Unless otherwise specified, devices only support 2.4GHz Wi-Fi. The mixed networks of 2.4GHz and 5GHz have a low probability of being successfully paired, so please make sure that the Wi-Fi connected to your phone is 2.4GHz. Most routers have a network frequency band of 2.4GHz. You only need to separate the mixed networks of 2.4GHz and 5GHz, then you can normally connect the device to the 2.4GHz network.
Note: Only devices that explicitly state in the manual that they support 5G wireless network support 5G wireless network.