In the UK do the Mini's fall under the BMW moniker? Here (and in most places), Mini is it's own Make, and One would be the Model. I see the 2012 Mini One available to choose from.
You can edit your vehicle here:
http://www.fuelly.com/driver/cyclist/vehicles/bmw/edit
Also, while you're there switch your Reporting units from Gallons (US) to Litres.
Your reporting units are set on a per-vehicle basis, so it doesn't matter what your other vehicles were set to.
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