In most cases, you can't switch retailers with an unmetered supply.
Most unmetered supplies (UMS) are linked to a specific retailer based on location and the distribution patch you’re in. There are some exceptions, for some devices. You’ll need to ask your retailer about your particular UMS device.
Where is Origin the local retailer?
Origin is the local retailer across the following distribution patches:
Victoria – Citipower and Powercor
New South Wales – Essential Energy and Endeavour Energy
Queensland – Energex