Smart meters and off peak tarrif

So i had a Smart meter installed and applied for an EV tariff from Scottish power. They put me on that tariff, but my smart meter and in house display still shows my old tariff price (27.53p kwh Opposed to 28.9p peak and 7.2p off peak between midnight and 5am) and clocks up my charges using the old tariff. I.e. I charged my batteries between midnight and 5am (using the old tariff before I started the EV tariff to test the system) and in the morning the display showed around £5 per charge when it was 27.53p per kwh.

Now I'm on the EV tariff which is 7.2p kwh, but my display is still showing around £5 per charge when I look in the morning.

My peak rate is now 28.9p kwh, but my display and smart meter lcd still shows 27.53p which was the old tariff.

I have been on the EV tariff for 3 days now.

I chatted to Scottish power, and they said that it's the smart meter that sends the data to their computer to work out the peak and off peak charges, and I'll see this on my bill,

They also told me that my in house display can not show the off peak charges, and still clocks them as peak rate, hence displaying £5 odd per charge, opposed to what should be a quarter of that price.

Is this normal? My in house display is basically useless if that's the case!