Terrible lost baggage service

On route to Mauritius from Cape Tow, our bag was lost, then found 4 days later by Air Mauritius still in Jhb. Despite our immediate request and obvious description of the bag it was only found when we sent a photo of the bag, it seems no effort to find it based on our very obvious description. Now we’ve been waiting another 2 days and counting for it to arrive in Mauritius. We enquired this morning and it had still not left Jhb - ***? They made no effort to call and explain the delay. How can they get away with such terrible service?