darthjack

I have a ford fiesta 2006 with the 3 button remote key.
In the manual it says press the lock button once to lock, the direction indicators will flash twice as confimation.
To activate double locking press the button twice within 3 seconds, the direction indicators will flash twice as confimation.
My indicators dont flash (I'm sure they used to)
Does this mean i have a problem with the key fob & also what is double locking?
I dont like the idea of one day not being able to start the car or it unlocking itself ,as the key fob in knackered.

edit: door will lock after first press, but wont recognize the second key press, thats why no flashing indicators and no double locking
How can i fix this?

Thanks.