<prompt> Human: Hi All,Im 34M, have a wife and a kid. A week ago I received a surprise 300 bill from a dentist who claimed I was 1 60 days late despite this being the first notice of the bill so they were charging me 100 more, 2 Was a result of them billing my insurance months after dental service and months after said insurance was canceled I switched jobs and 3 they wont budge on the 60-day late fee for service, or any of the bill, and want full payment or are threatening to take this to collections and add more to the bill. I dont like to be bullied or extorted, and likely wont be paying this on principle.We live frugally and have a fixed-rate mortgage on a home at 3.65 interest. We have a pretty significant nest egg 500k and never take out loans for anything, including cars all bought used, all cash. I work in tech and have a stable career, my wife works in science and also has a stable career.Im struggling to find a reason to be threatened by this hitting collections - am I missing something? Since we never take out loans, already have a mortgage and otherwise pay our bills on time, I cant see a reason why we should feel threatened by this in terms of credit score.  <response>: 1 60 days late despite this being the first notice of the bill so they were charging me 100 moreDid you sign anything with the dentist that says they can charge this 100 fee? If not, they likely cannot just add on late fees. 2 Was a result of them billing my insurance months after dental service and months after said insurance was canceled I switched jobsIs your dentist in network? Insurance companies generally have rules that their in network providers need to follow with billing. One common rule is that if they dont submit the claim within a set period, theyre out of luck. Id follow uPersonal-F s advice and contact your insurance at the time of the service. Tell them the situation and ask what you should do. 3 they wont budge on the 60-day late fee for service, or any of the bill, and want full payment or are threatening to take this to collections and add more to the bill. I dont like to be bullied or extorted, and likely wont be paying this on principle.Again, did you sign anything that says they can charge you additional fees? Depending on the state, a collection agency cannot add fees unless the original agreement allows them to do so. It sounds like your dentist may have switched medical billing firms and the new one is playing hardball with the accounts they have found open. Who did you speak with? Someone actually in your dentists office? Did you go there in person and speak with the receptionist? If not, I would do that and in no uncertain terms tell them that they need to fix this situation now or give you your records so you can switch dentists. 