Five years earlier, they’d told contracted transportation providers in metro Denver to bill the state as if the providers were specialty ambulances. In reality, the pick-ups should have cost $65, legislative staff told lawmakers Tuesday. “We paid 10 times what we were supposed to pay?”It’s unclear how much the incorrect billing guidance has cost the state’s Medicaid program. Legislative staff asked Medicaid officials why they “didn’t catch the error for five years,” according to the report. Because providers were following instructions from HCPF, which oversees Medicaid, the excess money can’t be clawed back or pursued, legislative staff told lawmakers Tuesday.