Al4 automatic transmission shifting at high speed

Good day guys. I don't have a problem in the city with my 2005 model 307 al4. But when I take the long road, my problem starts after about 40 km. When I slow down on a long road and want to accelerate again, it throws the gears at 4000 rpm and when I take it manually, D stays fixed. I am not getting an error on the screen. Transmission was overhauled 4 months ago. It existed before and after the revision. Why does it happen to anyone?