HOW TO DISABLE SYSTEM INTEGRITY PROTECTION (SIP) OF YOUR MAC?
1) POWER OFF YOUR MAC
Turn off your mac through the normal shutdown option in the macOS system
2) HOLD ⌘+R
Hold ⌘+R to boot into Recovery Mode of your mac.
3) OPEN TERMINAL
Open the terminal ( Utilities > Terminal)
4) RUN COMMAND
Enter "csrutil disable" without the quotes and press enter...
5) REBOOT
Reboot into macOS and run MagicClock again...