The Macbook Pro's touch bar is a convenient feature that allows you to quickly access important functions from the keyboard. If your function keys are not working properly, it could be caused by several things. To start troubleshooting this issue, please follow these steps:
1. Check if there are any software updates available for your device and install them if necessary.
2. Restart your Macbook Pro to see if that resolves the issue with the function keys on the touch bar.
3. Check System Preferences > Keyboard > Shortcuts to make sure all settings are correct and up-to-date for each of your app shortcuts and system items such as volume or brightness controls in particular have been set correctly as described here: https://support.apple.com/en-us/HT203592
4. Ensure none of the physical buttons around your touchbar area (such as F1 - F12) have become stuck or disabled which may cause an interference with active use of those same control key commands through their virtual version on the Touchbar itself .If so, try external cleaning methods like compressed air or simply reinserting each individual key into its proper placement on the keyboard again until everything appears normal again after further testing by running apps used daily while also keeping an eye out via Activity Monitor app (found in Applications folder).
If none of these steps resolve your issue with function keys not working, we recommend contacting Apple Support directly for assistance in diagnosing any deeper issues causing this problem specifically related to hardware components within both Logic Board & I/O board assembly lines found inside MacBooks themselves since they will likely require more technical expertise than what can currently be provided over online forums such as this one!