So I have had an official reply from
"Thank you for your email, and I am sorry you are having trouble with CCleaner for macOS.
Please allow me to clarify that this is the expected, and largely unavoidable, behaviour in this version of the software, however. This occurs when you are Cleaning ‘Safari Cookies’, 'Logs' or ‘Directory Service Cache’, so if you have both of those rules checked when running a clean you will be asked twice to enter your password. We’re doing this so that we can clean things properly and thoroughly, as you’d expect from CCleaner
Previous versions of CCleane