have you had your car insurance cancelled

i was insured with a known company.i missed a direct debit so i went into the SHOP to pay it...and to only get told THEY CANT TAKE MONEY OVER THE COUNTER..i had a bit of a ding dong with them,and then couple of days later i got stopped by the police and they checked my insurance and they got told that,i wasnt insured .i explained i wanted to pay and they wouldnt take counter payment.That didnt matter he took my car it got impounded and i had to pay £120 plus 40 a day i couldnt afford that so i lost the car,when it went to court they let me of with a fine but i still got 6 POINTS..and there is noway il ever be able to afford a car because my insurance payments would be sky high....i want to no WHY COULDNT I PAY OVER THE COUNTER????????...i went to pay my insurance and a well known company said WE DONT TAKE OVER COUNTER PAYMENTS how pathetic x