I would have felt the same way BF, especially if I got something like that late on a Friday

I get very anxious about things like that. I know you have left messages. I wouldn't leave anymore, but I would keep calling until you get living people. That's the only way you are going to get answers, get the matter resolved, and get some relief from your anxiety

These types of things can look scary, but it's probably not the final verdict. Call the insurance company and ask what the code means. The pdoc or therapist who provided the service and whoever requests referrals for you (PCP's office staff?) should be helpful in getting things straightened out for you