I habe received numerous letters from a collection agency regarding a XXXX bill that I do not owe. I replied several times including copies of bills that show there is a XXXX balance, but I continually receive letters that they checked on this and that I still owe this bill. I have now wasted so much of my time speaking to both the billing office at the doctors office and speaking to this debt collector and writing letters that it has become ridiculous. It is not the money but the principal of the matter that I should have to pay a bill I do not owe. Also I am worried about my credit, which I am trying to reestablish after a bad credit history due to a criminal act. Please help me with this.