Airlink no help very unprofessional

Very unprofessional and conduct by the airlink staff at OR Tambo airport. I arrived at closing time at the boarding gate which was still supposed to be open. Thus I missed my flight, one man Donald tried his best to help me but no one answered his calls on the radio for 10 minutes. After I missed my flight, I started trying to get a refund to book another flight, but the staff booked an incorrect tome that I arrived at the gate to cover for themselves and thus I am still trying to get a refund. Nkululeko Mnguni from customer is not willing to assist with the refund and I have asked for a supervisor or manager to contact me 2 days ago and still nothing. Very unprofessional and downright thievery for not refunding me after this incident.