if i remember correctly yes i have install the slim version
about the earlier version, i tried 5.14 but it seems that my pc shows a box that says i need to use the latest version of it.
might as well as reset my pc, i resetted it this morning so it wouldn't hurt to uninstall ccleaner by doing this (but i wonder does resetting my pc uninstalls ccleaner?)
It's a bit drastic to reset your PC - I'm assuming you mean to start fresh again with a clean install of Windows, I wouldn't do that just to get rid of CCleaner.
Make sure there's no CCleaner processes running when attempting to uninstall, and if you still can't uninstall it there's always a manual uninstall method which you could get away with doing since it isn't hooked deep into the system like a driver, etc. Manual uninstall simply details just deleting it, and if you know your way around the Windows registry you could also manually delete the CCleaner settings in there too or just leave them if you're not comfortable editing the registry.
Unfortunately i have already reset my pc. But ccleaner no longer exists on my laptop (search in apps & features, search bar and can't find it) so what's done is done. The problem is resolved, but I appreciate the effort to help.