HDMI CEC not working since upgrading my Pi

Im sure this will have a very simple answer…

I recently updated my Pi from a Pi3 to a Pi4 to use as my media player (LibreElec/Kodi). This was predominantly for the option to play 4k.
However, since changing over to the Pi4, i have lost the ability to use my TV remote to access the Kodi functions through the Pi. Im wondering if it might be something to do with the fact that im using an HDMI adapter cable to convert my HDMI existing cable to HDMI mini? The Kodi player does popup the CEC module when it first boots up, just as it did with my Pi3, so i dont think thats the problem. If its my HDMI cabling thats at fault, is there anything specific i should be looking for in the specs when buying a replacement?

Thanks in advance.