Altech Netstar *******ly deducting monies

My 24 month contract lapsed and I cancelled it in writing in March 2015. Despite 5 calls to the offices of Netstar to complain that monies were still being deducted they continued to deduct monthly premiums after cancellation date (******* deductions). I wrote numerous mails requesting their director `s details and finally after threatening legal action Cairn (a manager) called me. I received written confirmation from an account person (Natisha) my contract had been cancelled 4 months previously and assurance that no further debits would be made to my account. Further deductions were made every month, incurring transaction fees each time. Netstar finally refunded me the previous deductions (not transaction fees) and again assured me no further deductions would be made. Naturally the next month another deduction was made and not refunded, despite more complaint mails. They have not refunded me and appear to be ignoring any mails I send or requests for director `s contact details. I have been a retail executive for many years yet have never seen such shocking service in all my years in business. This must impact seriously on their service levels. Disgraceful!