Unexplained change in behaviour of CCleaner Pro

My OS is Windows 7 and I have CCleaner Pro 5.08 installed. Aside from my running a clean now and then, I've been used to CCleaner popping up a message every few days, saying that #GB of free space can be reclaimed - click here. It's obviously a very useful function, and there were no problems with it, but I've not had such a message for a while now, so I'm wondering why. Can anyone help?

Have you checked if monitoring is still turned on?

Open Ccleaner..Options..Monitoring

Thanks for your speedy response; apologies for my less than speedy one!

Monitoring is turned on with instruction to prompt to clean. I see that the minimum amount is set at 0.2 GB, so, presumably, CCleaner has simply not found an amount above that level for a while. I should have checked those settings before posting, so apologies again. (Trying to do too many things at once over the weekend, so brain was a bit befuddled!)