Quoting from the GitHub’s page:
The exploit is a race condition that requires precise timing and several other conditions to be met for it to trigger successfully. As such it can take a while for that to happen.
Which means that, sometimes, you run the code but it simply fails. When it happens, you can turn off the console and try again.
DevCuber@sh.itjust.works 7 months ago
If i remember correctly, some memory address that needs to be overridden by the exploit is randomized on startup. The only way to find it is to just write to a random address, which often fails