Fixed: 433MHz RX issue

I’ve set up my Arduino as per the instructions on here:

I’m using the exact same keyfob too, as it happens.

However, when I press 3 of the buttons, nothing happens, I’m only getting a signal from one of them (button “C”)

Received 5625100 / 24bit Protocol: 1

I get nothing from any of my car fobs (which being Japanese are supposed to be on the same frequency).

Would an antenna make a difference? I can receive the signal from button “C” from over a metre away (haven’t tried any further)

Edit:
Turns out, the keyfob wasn’t programmed with anything. The original instructions didn’t work but I managed to find some more:

a. Delete the original code.
Press (A) and (B) at the same time for 2 seconds, the LED will flash and extinguish immediately, at this time, keep pressing button (A), and release button (B). Now press button (B) 3 times within 3 seconds. When the LED flashes quickly, ALL codes 4 have been deleted. Now if you press any button, the LED will not flash at all, that means the code has be deleted completely.

b. Copy the remote.
Make the remote to be copied and copy remote face to face, press the same button of the both remotes at the same time for 3 seconds, the LED will initially flash 3 times slowly. It then flashes quickly, meaning the code has been learnt. Do the same operation for the other 3 buttons.
Attention: during the learning, pls make two remotes as close as possible, press the button of the remote to be copied a little longer to make sure the code has been learnt successfully.

Using my car remote, which is obviously on a rolling code, I’ve programmed each of the 4 buttons with a different code which now gets picked up on the Arduino. Oddly, my car remote doesn’t show anything on there…