Ever since we began filing claims through Simple Practice, we've had problems with Horizon BCBS (22099) claims being denied out-of-network even though we are an in-network provider. We did not have this issue before when we paper-billed, and after dozens (no exaggeration) of phone calls, we are tempted to go back to it. No one at BCBS can figure out the issue. The response is always the same: "Everything in our system indicates you are in-network. I don't know why the system is denying out-of-network." We've had supervisors involved, contacted provider relations, but no one at BCBS can help us. One claims rep figured out that it is primarily happening with two BCBS plans: Omnia HMO and Advantage PPO. Since this was not an issue until we began filing through Simple Practice, we think it might be a clearinghouse issue. Has anyone else had this problem? And if so, were you able to resolve it?