I believe this requires that you have purchased the Avast Cleanup Product, see the Avast Cleanup sub-forum
https://forum.avast.com/index.php?board=63.0.
Have you purchased Avast Cleanup ?
If so I suggest posting your question in that sub-forum.
I don't like it when the smart scan does scans of products that you either haven't purchased or that you haven't installed. They are trying to get you to purchase the paid product, the free version just reports.