@Wayne-TP That makes sense, I have reset all the data for the plugs as a result. Also thanks for the calculation, I understand why as rates can be variable.

I have bought 4 of these plugs and while they all work, the cost calculation in the app is incorrect. I have inputted the price as £0.29 the kWh is 0.187 which should be £0.05 in cost. Yet it shows...