how do i disconnect my immobiliser in renault clio?

i have a renault clio and the two keys keep untuning from the immobiliser when I get them fixed. I brought the two of them to a renault dealer and he tried to tune the several times. One always works all the time but the other one untunes. Then when you get that one tuned, that one works perfectly and the other one starts causing trouble. I think the best way to sort it is to cut the immobiliser wires or somthing like that, COULD ANYONE JUST TELL ME WHAT WIRE TO CUT, OR WHATEVER WAY LIKE THAT PLEASE!!