Steps to Solve Private DNS server Issue on Android
1. On your phone, open the Settings menu.
2. Next, tap on Network and internet settings, scroll down, and tap on the Advanced option.
3. Choose the Private DNS option from the advanced menu.
4. In the pop up window, choose the Automatic or Off option.
5. Next, tap on the Save option to save your settings.
6. You should now able to connect to the Wi-Fi network.
(For S10 Plus must go to settings| connections |more connections settings.)
*If your device has the setting "Random Hardware Addressing" or "Random Mac Addressing" enabled, then you will need to disable this option.*