Uber continually cancel or delay pickup

What's going on with Uber South Africa? We select drivers who are closest only to have them cancel because the trip is deemed too short Or they accept a job when 5 minutes away only to up pickup another customer keeping us waiting 25 mins. Drivers have also become aggressive and also driving dangerously. South Africans don't have much in terms if local service but we shouldn't have to take this treatment from Uber when they would never get away with it abroad. The drop in standards is not acceptable.