iPhone

1. Launch the Settings app
2. Tap Wi-Fi
3. Tap the info button next to the APNK WiFi network
4. Tap Forget this Network
5. Tap Forget

Android

1. Launch the Settings app
2. Tap Network & Internet
3. Tap WiFi
4. Tap the Cog button next to the APNK WiFi network.
5. Tap Forget