Lude Generation

Okay so my key fob does not work, however out of the blue the other day it did work, but just the once.
I've tried reprogramming it a few times and it does activate the locks on the 4th cycle but it seems to forget the key instantly. Any ideas on what to check first? Thanks

Apologies if this sounds like treating you like an idiot (I don't mean to) but... Are you sure the battery isn't just flat?

Yeah the battery's good haha, the led flashes when I push the button and I've also tried a new battery as I thought maybe it was dying

have you looked over the circuit board to see if all the connections are good , common fault with remotes is bad or loose connections on the battery and buttons

Well the light flashes so I'm assuming it works on the key end, does anyone know where I can in the car? There mus be a loose connection, right?