My partner and I live in a one bedroom flat. We are on holiday and are currently away for almost 2 weeks now. But I just checked our electricity usage and it’s so high even when there’s no one at home? Some of the appliances are plugged in at home such as fridge freezer and router. We have the towel rack heating on in the toilet. None of the radiators are switched on. Anyone has any idea why this is happening?  

Have you checked if these are actual readings or maybe estimates? Even with a smart meter, sometimes readings do not get through and in that case they will estimate your usage. Your last graph with the same usage each day looks exactly like that.