1999 honda accord automatic transmission problem

My 1999 honda accord lx 4 door sedan has a problem that my dealership
cannot fix.
The problem is that when the vehicle is hot after being driven about 20
miles the vehicle will not move in reverse unless first shifted into
neutral then back in reverse. it will then only move as long as the gas
pedal is pressed all the way. as soon as pressure is released a little the
vehicle stops as it the brakes has been applied. in order for the vehicle
to move backward the whole process must be started over. Has anyone
experienced this and what is a possible solution.


rm