Fuelpecker issues

Last month on receiving a Fuelpecker receipt 11 days after an alleged top up, I noticed that the fuel used was Diesel Supreme+ @ £1.659 a litre.  It seems that volume of diesel fuel pumped was 34.99 litres at a cost of £58.05.  As we have a Nectar card and points is per litre I always round it up. 

This immediately got my attention as you cannot get normal diesel at anywhere near the £1.659 price probably anywhere in the country.  Even with a discount the lowest price for normal diesel is £1.79 never mind Supreme. 

On checking further on the date when the diesel was supposedly pumped into my vehicle, my vehicle was at a towbar fitter's workshop having a new towbar fitted and my fuel card was in my pocket.  The time for the fuel pumped is recorded as 1457 hours, but I have proof that the vehicle was dropped off at the towbar fitter at about 12pm and also a receipt from the towbar fitter which shows the time I collected the vehicle and it is much later. 

I have contacted Fuelpecker customer service on 30th Aug and no reply.  I then contacted Fuelpecker accounts on 7th Sept asking for details of reg number, mileage and place where the "offence" took place.  Still no reply from either of them regarding what is obviously a fraudulent transaction.

To clinch it, on the 21st which is 3 days later I filled up the vehicle with 77 litres.  If I had put 39.9 litres of diesel into the tank on the 19th, there is no way I would have been able to fill up with 77 litres 3 days later as the maximum mileage between 19th and 21st was less than 20 miles.

How many of you keep a record of fill ups and would pick up what appears to be a fraudulent transaction?  This transaction of £58.05 has wiped out any savings we have made over the past year! 

As Fuelpecker are not responding I am unsure how to progress this further.  Not sure if this should be reported to the police, CAMC as it is a CAMC product or bank, but without an indication where the fuel was purchased, could cause issues.

Can anyone advise?  Thanks