Can the fix only be done by Renault if it's still in warranty I presume? Mine does this and has only done it since I fitted my new grille which I had to take the bonnet sensor out to do.
i played a game today... i tried to make mine do it.
I was able to make it beep 3 times if i turned off the engine, quickly get out, slam the door and lock within a few seconds...
if i was a normal person and switched off, undid my belt, got out and locked normally it was fine.
conclusion: slow down!