Netstar ripping me offf

I think Netstar is trying to rip me off. I had an insurance contract with budget for my car which also include the tracker from Netstar. I was making the payment to budget all this time and in January I asked Budget to freeze or cancel my contact because I am current experiencing financial problems. They did that and advised me that after 3 months the policy will lapse, I was not advised to phone Netstar also to cancel the contact with them and I also thought that if I have cancelled with Budget they will notify Netstar. Now Netstar has sent me their statement, saying i owe them from March till June. Why only sending me the statement now but not in January, why only changing me from March but not from January. Please stop ripping us off.