cvt warning light

when i come to start up all lights light up then i start the car as soon as i put the car in drive the cvt warning light comes on the car runs ok but when i park the car at the local shops after i get back to the car it starts up no problem after about half a mile the cvt light comes on again and stays on what do you suggest i do its got new brushes should i check the inhibitor or any thing else,its a 1998 micra thanks cheers