A project manager did not release the resources. A project manager not releasing the resources could most likely be the cause of this issue where several employees' allocations from the past month appear to be 200% even though they are only assigned to a particular project. Releasing resources is a process of freeing up or reallocating any human or material resources that were used for a project after its completion or closure.
Releasing resources can help to update the resource availability and utilization records and avoid any conflicts or errors in resource allocation or reporting.