CPT 51798 - Denial by Blue cross blue shield

[Medicalbiller1978]

CPT 51798 is denied by Blue cross as noncovered. Although, when billed with CPT 76775 , 76775 does get paid, but not 51798. I referred to list of dx we can bill 51798 with and I am billing correct dx. Not sure why its denied every single time.
Any pointers?

[rdmoore2003]

may not be covered on members specific plan.

[Michele]

Have you called customer service to ask them to elaborate on the denial?