Transmission will not engage
 

Hey , thanks for reading. So im taking off at a green light and get to about 30 mph. Im a normally driver. No heavy foot at all. I notice that my car starts slowing down. I look down and my rpm's seem to be rising... Weird enough. I pull over and put it in park and shut it off. Restart the car and it starts up perfectly. No weird sounds , smells , nothing.... Put the car in drive and its like im in neutral. Put it in reverse , uggg the same thing. I cannot engage in any gear at all. I checked the tranny fluids and its clear and full. ANy advise would be appreciated. There has been no signs of tranny slipping , irregular shifting at all. Just stopped engaging. Thanks in advance. My email is Mik543@yahoo.com if you have any advice