Keep waiting. If you have a lot of files to sort through it can take a while. The app is conducting a deep hash scan of each file to confirm whether it has any EXACT duplicates. This is the only way to have 100% accurate results.
If you are experiencing excessive scan times and don't have time to wait, we recommend that you scan your folders in batches rather than everything in one go.
Scan times will vary depending on the performance of your Mac and storage device. The process of scanning for and detecting duplicates is very intensive as it requires the hash strings of each file to be compared to one another. We have opted for this approach as it is the only method to determine with 100% accuracy if files are duplicates of one another.