purgeable disk space cannot be used
Hi, after I did a lot of housekeeping to delete and remove unwanted files, my MacBook HD shows 326GB available, with 265GB purgeable. However, when I try to copy a folder with 80GB to the HD, it says there is short of 20GB of disk space. I tried many ways to get rid of the purgeable files but it just can't be done.
Would be grateful if anyone could help advise.
Many thanks!
MacBook, macOS 10.13