Private Address is turned on by default. It has to be disabled for Sincoolka Wi-Fi networks.

1. Open the Settings app, then tap Wi-Fi.
2. Tap the information button (i) next to a network.
3. Tap to turn Private Address off. If your device joined the network without using a private address, a privacy warning explains why.

This is a part of an article https://support.apple.com/en-us/HT211227 that has been copied here on September 4, 2022, with slight modifications. The copy is for the purpose of people with no Internet connection.