That is their best network and a good plan-it's too late to get an agent to help you this year, you can engage with one during the next Open Enrollment Period for 2017. No agent is going to take this on without any compensation for 2016.
There are third party companies that will engage with consumers for claims review and recapturing money that was billed incorrectly. I have no experience with any of them but a Google search will get you some options.
