I would keep your insurance certificate on you (or at least your insurance companies contact details), just in case the Old Bill pick you up for it (your reg may set of the ANPR alarm in Traffic cars as they're linked to the insurance database) and you don't really want to be left on the kerb while they impound your car. Also, contact your insurance company to find out why!
There are anomalies, hopefully yours is an easy one to sort.