1997 ford 450 tranny problem

good day to all i wanted to see if some one can give me an idea someone in transmision tec i have 350 e40d trans this trans has been replace 2 times on this truck and i just rebuilt it saturday drove it 150 miles no problem ,, today went to drive it again stuck on 2 gears again this is the 4thntime has some may know whtas wrong iam thinking chnging my computer and rebuilt it one last time if i can get some advise here from some one :banghead:

Replace the valve body.