I am fairly new to substance abuse billing and am in a rut that I can't seem to find my way out of. I haven't had any problems with my RTC claims because they haven't required any HCPCS info but my PHP and IOP claims are a different story. I am using rev codes 0913 (PHP) with HCPC H0035 and rev code 0906 (IOP) with HCPC H0015 and I am not able to get them passed the clearing house level, they are all rejecting there. The only info that they will give me back is that I have missing or invalid information between boxes 42 - 49. My entire claim is filled out the same as an RTC claim other than these boxes. If anyone could help it would be greatly appreciated. I am really in a time crunch. Please and thank you!!!