KIA CARNIVAL 2001 BOX IN DIRECT FLAVING LUZ

Hello friends,
I have a carnival kia 2001 Automatic Benchinera 50mil kilometers.

Derresses about 60 km/h something sounds as if
the speed is broken down and begins to flash the letter N (neutral) being direct.
In other occasions only flashes intermittent
(direct) without noise or anything.
The fault is not permanent. I turn off the engine I wait a few minutes and as if nothing for several days.
Hopefully they can help me.
Thanks in advance