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2 Fixed typos.
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Wi-Fi passwords are synchronized via iCloud keychain. That's why your iPhone also knows the password. Try deleting this network from Preffered NetworkPreferred Networks.

Also delete item from your keychain. In Keychain Access.app select iCloud keychain, find the item with the SSID (network name) of your neightboursneighbor's network and remove it (Right click -> Remove).

Wi-Fi passwords are synchronized via iCloud keychain. That's why your iPhone also knows the password. Try deleting this network from Preffered Network.

Also delete item from your keychain. In Keychain.app select iCloud keychain, find the item with the SSID of your neightbours network and remove it (Right click -> Remove).

Wi-Fi passwords are synchronized via iCloud keychain. That's why your iPhone also knows the password. Try deleting this network from Preferred Networks.

Also delete item from your keychain. In Keychain Access.app select iCloud keychain, find the item with the SSID (network name) of your neighbor's network and remove it (Right click -> Remove).

1
source | link

Wi-Fi passwords are synchronized via iCloud keychain. That's why your iPhone also knows the password. Try deleting this network from Preffered Network.

Also delete item from your keychain. In Keychain.app select iCloud keychain, find the item with the SSID of your neightbours network and remove it (Right click -> Remove).