slipping, flashed D5 light for a while and not going into gear now

What is your question?

The transmission start to slip at the beginning, flashed D5 light just for while when the car was in D4 mode.By turning off and then back on got rid of D5 flashing. But interestingly after parking the car at roadside the car didn't want move into any gear and after a slight push the car accepted a gear in D5 mode. Now again the car doesn't want to get into any gear. I don't know what could be the problem?