Why does my iPhone 13 only connect to 5G but shows it's connected to Wi-Fi in settings?

iPhone 13 suddenly stopped connecting to Wi-Fi and only connects to 5g but in settings it shows checked that it is connected to Wi-Fi

My iPad works fine on the same on the same Wi-Fi and my wife's iPhone works on the Wi-Fi network and my windows laptop works on the Wi-Fi.

When I restart my iPhone, the Wi-Fi connects for about 5 seconds then switches to 5g.

It's just my iPhone

[Re-Titled by Moderator]