Cartrack worst customer service!

cartrack by far the worst customer service i have ever experienced! ive been a loyal customer for over 4 years Ive been paying them more then my intended premium every month when i queries this it is said my account is in credit i asked them to refund my money back and still nothing a month later over 7 phone calls and numerous customer service people Ive spoken to NOTHING!! i get phone calls dropped in my ear, no reply to my emails this is exceptionally frustrating!!