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We have tried to reproduce the scenario with a simple schedule control sample. However, we are unclear of the use case that the conflicts of DateTime when the appointments are added. So, we suspect that the issue might be occurred due to some other ScheduleControl settings or the difference between replication procedure. Please refer to the attached sample and let us know the code that we are missing to reproduce the issue. If the issue is occurred in the provided sample itself, please share a simple video or screenshot that demonstrates the replication procedure.