Hey Tropicalbenji,
Can you try a couple things for me? First of all, connect your controller to a different USB port and also try a different cable.
Its also a good idea to go through these steps:
serato.com and make sure that those buttons are sending a MIDI signal.
Feel free to attach a screenshot of the MIDI signal and I'll try a Twitch here and make sure we are sending the same signals.
Let me know how you go,
Cheers, Sam