Health insurance: Two doctors in one day?

I'm having a situation with our health insurance and I was wondering if anyone had any advice. The other day I went to urgent care because of a medical situation and the doctor at the urgent care referred me to the ER in a hospital because he felt the situation was grave. The claim made by the urgent care to my health insurance company was for only like $100 but the claim from ER is almost a thousand, however, the insurance company is using a technicality that I was unaware of in saying that because i went to urgent care first, and then was sent to ER, that they are only obligated to pay for the first claim made for that particular day (the urgent care), as they will not pay for two doctors visits for the same day. They received the urgent care claim first and so now i am stuck with a 7-800 dollar bill from ER without any payment from my insurance; is there any way I could work around this? Could I have the urgent care somehow revoke their claim? Its frustrating.