Did you fit it yourself or did you have someone come in and do it for you?
If it was you was the wiring the same or did it come as a conversion?
Ok normally when you get this problem its either a faulty regulator or the wiring is different from the original switch.
As its a new switch i dont think it will be a fault switch.
On the switches there will be a part number on the switch themselfs. Can you let me know the numbers of both switches please.