the button on my key has never worked, it may have done once but never since, why is this can anyone help?

If you open it up you'll see it has a battery inside. Replace the battery and it should work again.

tried that

What do you drive again? Is it supposed to have remote central locking?

its a Bravo,
the key locked the car once but never did it again!

Is the little red light flashing when you press the button? Maybe it's a fault in the car rather than keyfob.

it was doing last night but it isnt today!! its a bit tempremental

The microswitch inside the key and the small actuating lever on the button are both likely to fail. If you open the key check to see that the lever operates the switch and that the red light comes on.