Delta Airlines Review

I sent a tour group of students with special needs out on Delta (against my better judgement but that is who the company booked us on).  First they did not have reservations for two of my TICKETED students, we had to talk them onto the plane.  One of the students was the first one who paid for the trip.  They did the same thing to this SAME student two years ago.  THEN they refused boarding to one of my students saying his passport, which expires in 3 months, was not good enough.  It had to be good for another 6 months.  We later find out that it has to be good for another 30 days so this poor kid gets denied boarding.  They acknowledged their error but did not do much for us until the father started yelling.  They finally arranged a MUCH later flight for the child who now had to travel to a different country alone, change planes and meet up with the group.  They agreed, after a bunch of yelling, to provide someone to escort him between flights for free.  This is the second time our group used Delta and the second time we had problems.  On the first trip they bumped 6 students of a high school group, AFTER they had checked in and confirmed and said they could go the next day.  This was after all the parents had left.  They ended up getting them out later that night but these 6 kids missed an entire day of the trip, as will my two who are going right now.  Delta really needs to get their act together.