Nando's delivered an eaten chicken

My heart has been dismayed by the appalling customer service I experienced at Nando's in Lonehill. On the 18th of November it was my birthday and I decided to spoil myself with a meal. When I opened my order the chicken wing was eaten. I had to throw it away due to health and hygiene reasons. I have sent my complain to the Facebook chat. They said the manager from Lonehill will contact me, she did but I told her I was in meeting and callback at 4pm, she didn't. Went back to the Facebook chat on Friday and still said the Lonehill manageress will call you. It has been more than a week and still my issue is not resolved. Now I see why my chicken was eaten cause they don't care. I think some serious disciplinary action should be taken on both the manager and the Facebook admin there is no sense of urgency, proactiveness and the initiative to drive things yo resolution.