Your VM most likely has active snapshots. To find out about this, and whether it is save to consolidate these snapshots, please run ls -lisa *.vmdk from the command line to list the files in the VM's folder, and post the output in your next reply. Also let me know how much free disk space you have on the datastore on which these files are stored.
André
PS: Assuming that you just accidentally posted your question in the Skyline Health forum, I will proceed with moving it to the ESXi forum.
