How can l deactivate my mobiliser.... Renault clio 1.2 1999 S Reg?

How can l deactivate my mobiliser Renault clio 1.2 1999 S Reg.... RAC came and wire started my car .... now if l want to start my car l have to put the key in first and join wires together ...now then l get light on the dashboard and l use the key to start the key....
If l remove the key the engine stays running until l separate the wires..... Someone told me that the problem is the chip inside the key which needs to be programmed... l wanna sell the car l cant afford to buy new ignition
Please help......