Missing luggage for 3 days

Flew from Germany to ZA via Serbia and Abu Dhabi. Luggage didn't arrive with my plane on Monday evening. Borrow money and clothes from collegue as airport baggage enquiry won't help me. Tuesday morning at Etihad office I get a R 1000 (good but needed to go to airport again) and promise that luggage will be delivered to hotel where I stay. Today Thursday still nothing and they can't tell me where my suitcase is but promise it will be on next plane