Bus leaving earlier than suppose to

The Beacon Valley bus is supposed to leave N1 city mall at 6.30pm, but when me my two colleagues were walking to the bus stop and saw the Beacon Valley bus leaving the mall , when we got to the bus stop another lady told us that someone told her now that the bus left already, witch means it left earlier than 10 minutes early. We had to bolt home and pay R172, and I have a monthly. But had to give extra out, how can the drivers leave early, we were 4 ladies that were left behind. This is very bad service, we pay too much for this horrible service.