Meter tail not fitted into 'off peak' correctly

What sort of meter is/was that @chipp1a (previously)? If it’s a smart meter then there may be a record of timed use. Otherwise I’m not sure how you show how much was used when. 
There may be a way to show typical use over a period but not sure how that might be explored

Have a look at the meter readings page. I have an E7 smart meter and this is what I see:
  
 

The readings for the two registers are clearly marked, and they also appear on the billing page as an expander under Charges in detail. Of course, this degree of granularity depends on the frequency of submission - my readings are sent every half hour.  

If you see readings for two registers, the chances are that the correct rates have been applied. You’d see this in the billing history. If the readings for one of the registers are missing, it gets more complicated, but it may still be possible to reconstruct the usage pattern for the previous year. Did the engineer who installed the new meter leave a sticker on it showing what readings he was able to retrieve from the old one?

Hi, thanks for the replies. So the original engineer that attended advised that the cable to the off peak box was no connected and the box was sealed off. Two further engineers then attended and installed a new smart meter. I am unsure of the exact make or model of the smart meter. 

I have checked his energy bills and from 11th December to 10th January it has his daytime usage recorded as 441kWh (£189.94) and his night usage as 26.6kWh (£3.84). 

Considering this is a small one bedroom flat the usage recorded seems quite high? I don’t know if you would agree? 

Any more thoughts before I get in touch with them?

Have a look at this page on the website not the app

https://account.ovoenergy.com/plan

You should see Future Annual Consumption.

This is how much your father in law typically uses in a year, automatically updated as the smart meter sends readings

What does it say?

Ofgem publish typical domestic consumption values. For E7

Low 2400 kWh

Medium 4200 kWh

High 7100 kWh

For the period you mention he used 467.6 so 15kWh a day. Obviously depends on insulation, heating, cooking etc. but not unreasonable. He could easily use 1 kWh for heating an hour for example in winter in some properties. His winter usage will be dramatically different to summer.

I assume he doesn't have gas at all. 

Given the peak, off peak split it does look like he would probably be better off on a normal tariff? He doesn't look like a typical E7 user

Thanks for the response, it says 2786.8 kWh.

No he doesn’t have gas at all.

So what would you say was the issue with the E7 meter with the off peak cable not being in the meter? If it has still been reading the night time usage then it couldn’t have had an effect on it could it?

Doesn't look like an unreasonable consumption then. 

I will be honest i am not sure about what impact the cable has. 

As an aside how does your father in law use E7. Does he have night storage heaters that are setup to charge overnight? 

I can vouch for this. :)