Sometimes there is a process associated with Google Chrome running during the cleaning operation and this may cause Chrome cleaning to be skipped. All internet browsers need to be closed in order for them to be cleaned properly by CCleaner.
You may have a setting in Chrome that allows background applications to run after Chrome has already been closed.
To disable this setting, open Google Chrome> click Menu (3 parallel lines in top right) > Settings > Show advanced settings...> uncheck "Continue running background apps when Google Chrome is closed".
After you have disabled this setting, please run CCleaner again to see if the problem has been resolved.