Disgusting Mango Airlines!

Almost 2weeks after my initial complaint about Mango's poor service, inefficiencies, rude staff and constant delays I have yet to be contacted to discuss the multiple problems we experienced on our last trip as well as multiple trips before this. I keep being told over Facebook Messenger that my problem is being escalated and I would be contacted in 7 days. Now 12 days later still nothing other than a consultant Sia trying to call me once last week Monday and saying she would follow up with an email which a week later she still hasn't, or tried to call again. ] Almost every flight I have taken with you this year has been delayed. Our last trip which this complaint relates to (ref. QQLPGZ and QQLPFZ) was delayed on the way down due to one of your crew arriving late! Then as I booked through Momentum my husband and I had different booking numbers as your archaic booking system won't allow one flyer to pick Momentum and another not to. So 24hrs before I checked us in so we would be seated together, however upon arrival at the airport we were told that my seat had been moved, but the helpful gent at check-in moved us into 15A and 15B so we could sit together. Then upon boarding I was told that I had again been moved to seat 1C! No explanation and no help to rectify this at the gate so upon boarding the aircraft we spoke to the air-hostesses who were rude and unhelpful who just said the aircraft was full and they would see if they could help after everyone was seated which of course they didn't! Then on our return flight we were delayed for almost 3 HOURS and again our seats were separated even after i checked-in online but fortunately after being re-allocated at the counter we were kept together, we arrived home to a split suitcase which had been kept together by security tape!! I am totally disgusted at the lack of service I have received and your staff's poor training when it comes to customer service. My husband and I had unfortunately already booked another trip with you in September to Durban for my grandmother's 80th birthday. I refuse to have another trip ruined by your delays, costing me time with my family and causing us emotional distress. I would like these tickets fully refunded and I will rather book on a reliable airline like Safair, even at greater expense, and arrive on time and stress free. You offered us a voucher after our delay last Sunday, you can keep your voucher as I will never fly with you again and rather refund our next tickets if you would like to show any actual concern for your customer's satisfaction. I now still await your contact