Do you have a 2015 Macbook Pro or newer that features haptic feedback and it no longer works?
Perform an SMC reset with the Macbook turned on. Simply hold: control + option + shift + power button.
Your computer should instantly turn off. Turn it back on with the power button and your haptic feedback / force touch should now work.
If it does not work, try checking the trackpad settings under system preferences. Make sure “force click & haptic feedback” checkbox is ticked on.
If neither of these work, you may have a hardware issue.