Hi @Trin,
If you have been advised that you have to contact the previous owner to disconnect the internet, its due to nbn stating there is a current connection at the property.
If you have contacted the old provider, and they state that there was never an NBN connection at the property, you will need to provide a proof of address / proof of occupancy. This can be something like rates notice, utility bill, your lease agreement or deed to the property, please contact us by either calling 13 12 45 or chatting with us through our website or app to go through this process.
Kind Regards,
Hannah