I am a IT support officer in an enterprise environment and a user has
encounted the error:

"unable save or change as it is created by another modifier or is being used
by another user"

this user is the organiser of the meeting requests and this error occurs
when they have made a meeting and then at a later date want to reschedual the
meeting time/date.

there seems to be very little to no information on this error, does anyone
have any info that can shed light on this problem?