Insurance Cancelled

Hi everyone,
A family member has a black box in their car, and as they had been driving erratically this month, the insurance company have gone to take £45 out of the registered card as a sort of penalty. The problem has come where the card that is registered had expired, so the insurance company emailed them to inform them of this, but they had the incorrect email so no email was received. Therefore a letter was sent out saying they had cancelled the insurance. When speaking to the insurance company, they said it isn’t their fault the email address was incorrect and so they have just refunded the rest of the years insurance back and “washed their hands of it” so to speak. Question; is this legal? If not is there a body you could go to to complain? As you can appreciate, a young person with a cancelled policy, it going to be very pricy!
Thanks in advance!