Republic Services

I requested a 15-Cu Yd container was told only 30-yrds were available so I "pre-paid" $643.40 for container delivery and pickup. I returned within 30-days and figured that was it. Later received another invoice for $271.98 for "invoice charges" ($915.38). I contacted customer service and was informed that i was actually do a "credit" of ($371.42) ($643.40 less $271.98 equals $371.42). Credit was issued to me. Again, I assumed my account was clear and paid in full. Received a notice demanding I pay $444.47 (unsure where this total comes from) spoke to a Sr. Advisor who indicated he would get back to me within 3-days to provide a full "itemized invoice". Never heard back, assumed Republic saw their error. Just received an email in my old email account stating they would turn my account over to collections. How is it so difficult when I initially paid for my service in full prior to service delivery and Republic is unable to provide detailed charges to my account [protected]) / Inv (0615-[protected]). I refuse to pay for any service in which the provider is unable to provide a detailed invoice for services rendered. I'm wondering why each time I contact Republic I get a different amount owed. Until I see a fully itemized invoice with the original charges, credits paid in full, credits due to overcharging, supposed new charges and why, I will not be comfortable paying anyone any money. I paid (what I thought excessive) in full up front and in good faith, Republic Services has not provided a good faith itemized invoice.