Try SMC Reset
Try PRAM Reset
If resetting the SMC and PRAM / NVRAM did not work then try:
Navigate to ~/Library/Preferences/ and remove the following files.
- com.apple.driver.AppleBluetoothMultitouch.trackpad.plist
- com.apple.driver.AppleBluetoothMultitouch.mouse.plist
- com.apple.driver.AppleHIDMouse.plist
- com.apple.AppleMultitouchTrackpad.plist
- Com.apple.preference.trackpad.plist
More info: https://macpaw.com/how-to/keyboard-trackpad-not-working