Our pain management doc uses a drug screen dipstick test, CLIA waved, we coded 80101QW x11, for 11 different drug classes.

But Medicare has denied the claim stating Missing CLIA certification number.
As CPT 80101 is CLIA waived we have used QW modifier & also added the Product 'multi-CLIN' in 19th block of HCFA-1500 which is kept for Reserve local use. Do we need to add CLIA certification number ? If yes from where we can get it from Physician or from other source ?
Please help.