Transmission Hyundai Accent

Hi I have a Hyundai Accent Glsi 1.5 Mreg (1995) 5 door with 82,000miles on the clock when in neautral the car will not go over to 5th and reverse it will go into 1 to 4 but will not go past 3rd and 4th just stops it worked fine when I pulled out of the drive when I went to park at work it would'nt go into reverse or 5th i've had all the covers off inside and there's nothing stoping it going into 5th or reverse in the cockpit and all the cables are free to move as I disconected them at the gearbox side and tried themthe slector on the gear box will not move up please help as the wife is due to give birth anytime now so really need the car
many thanks
Chris