PLEASE PROVIDE CORRECT ICD10 CODE TO MEDICAL AID

My dad passed on more than a year ago and my mom is still receiving an account for payment from Vitalaire under account number ***. According to the medical aid Motohealth, Vitalaire has now for the past 15 months submitted the account with an invalid primary IDC10 code that apparently makes payment impossible. After numerous emails and telephone calls to Vitalaire and Motohealth, by my mom's authorised representative, the matter remains unresolved. My mom is now so distressed about this and asked for my assistance. If Vitalaire does not know which IDC10 code to use, they should contact Motohealth to confirm the code.