N.M. Stat. § 27-2-12.5

A. Medicaid payment for a medicaid-eligible patient shall be accepted by a medicaid-certified nursing facility from the first month of medicaid eligibility, regardless of whether the eligibility is retroactive. The nursing facility shall refund to the patient or responsible party all out-of-pocket money except for required medical-care credits paid to the nursing facility for that patient's care on and after the date of medicaid eligibility for services covered by the medicaid program. Within thirty days after notification by the human services [health care authority] department of the patient's medicaid eligibility, the nursing facility shall make any necessary refund to the patient or responsible party required under this section.

B. In any cause of action brought against a nursing facility because of its failure to make a refund to the patient or responsible party as required under Subsection A of this section, the patient or responsible party may be awarded triple the amount of the money not refunded or three hundred dollars ($300), whichever is greater, and reasonable attorneys' fees and court costs.