Incorrect Tariff on Electricity Meter, Estimated Gas Bill Very Wrong

Hi, since the new variable monthly tariff rolled out and energy prices increased your web page shows Electricity to be ;
Unit rate
27.63p per kWh
Standing charge
44.75p per day
My IHD and Meter both show this as;
20.306p/Kwh Fixed Rate
23.759p/day Standing Charge
This is clearly wrong and I cannot adjust for consumption based on incorrect pricing at my end. I like to know exactly what to expect at the end of the Month as I am on a tight budget. I live alone and work 8 hour shifts 4 days a week. I don’t expect to use a lot of electricity when not at home as I also have Solar PV on my roof hich nullifies consumption while I am out in the day time for a good dose of daylight hours.
The Gas meter tariff and IHD show the correct unit rate and standing charge BUT
My bills roll over on the 28th of each month from midnight and start again from Estimated bill £0.00 for electricity excluding the standing charge which quickly gets added, However - I turned off my gas boiler on the 27th April before midnight of the 28th and I also turned off my gas supply at the isolator to prevent any usage from minor leaks (if any) and because I don’t trust gas appliances while I sleep or not at home. I have not turned the gas supply back on yet or my boiler. No gas appliances have been used at all and the IHD shows ZERO gas usage from midnight of the 28th Apr up to writing this message at 16:00 28th Apr but the estimated Bill on the gas side says £3.98 !! How in hells name have I used £3.98 of gas including standing charge in 16 hours when the supply has been disconnected and no appliances turned on and the IHD says no gas usage??? Something is very wrong here.
Please can someone shed some light on this? Also the IHD says the Gas reading was updated at 28:04:22 - 05:48 while the Electricity updates every 30 seconds or so… ?
Many thanks.
Please correct my stupid old Smets 1 meter tariff and sort this mess out. I don’t trust my bills any more or the readings being sent or the integrity of the estimated billing.