British Airways - Sluggish Staff

On the 21st of June 2019, I was supposed to leave with my partner to PLZ on flight BA6249. On the way to the airport, there was an accident which caused us to have a slight delay, but we were still on time. We rushed through the airport to get to the counter within our 45 min window. We arrived 46 minutes before flight departure and were the only people in line. At the bookings counter, however, there were attendants standing there making jokes and blatantly ignoring us as we tried to get to our flight on time. Roughly 2 minutes later, a gentleman decided to finally help us, he informed us that we had missed our flight and that we had to rebook for the next available flight. This expedition was not a cheap one, we had to rebook on the next available flight which cost an additional R5000.00. At the time I was just in a hurry to get on my next flight and paid no mind to the incidences of the morning and didn't want to make a public scene. However, looking back on this experience, if the attendants had promptly helped us - as they were supposed to - we would have not missed our flight that morning. I think it is reasonable to inquire about this since I know that I'm not the only one that has been affected by tardy staff. British Airways - Please advise!