Open Question: Hospital Billing Question - Doubled Amount After found out had Insurance?

My Daughter had to visit the E/R on Spring Break - we received a bill for $295.00 as the adjusted amount due - assumed she had no insurance. I faxed her insurance information and it was filed. It was all applied to the deductible now the hospital wants us to pay $581+. How can they double the bill because she had insurance and it did not pay? If the first amount would settle the bill how can they change their minds? No wonder our premiums are absurd on medical coverage - this should be illegal, it is unethical. Who can I contact to file a complaint? She was in S.C. at the time. Please do NOT spam me with your web sites, job offers etc. This is Yahoo Answers not Yahoo Advertises. Stephen, sorry to disagree - I work for an insurance carrier and I did all the faxes, insurance contact. The hospital entered data into an automated system and hit file. 15 min. for a slow data entry clerk. It has cost them 3 stamps and ink for the statments but that is not worth double the billing.