1. Confirm if the remote control setting is enabled in your camera settings.
2. If your remote is wired, make sure it's firmly and correctly connected to the corresponding camera terminal. If your remote is wireless, make sure that the remote control batteries have sufficient charge.
3. If you're using a Bluetooth remote control, confirm if you've performed the correct pairing procedure. You may want to "forget" or remove the current Bluetooth connection and try to pair the camera and remote again.
4. Some remote controls have an ON/OFF switch or an accidental press protection switch. Check if it's unlocked.
5. Finally, make sure the remote you're using is compatible with your camera. Try to connect it with a different camera to see if it works.