When Flair Room Sense is enabled for a mini split you will have the option to define Quiet Hours for that mini split. The Quiet Hours are defined in the Settings for that particular mini split in the "Mini Splits, Window Units, and Portables" tab. Go to Home Settings -> Mini Splits, Window Units, and Portables, expand the device, and define the Quiet Hours you would like set for that device.
During the defined Quiet Hours, Flair will not send commands to the mini split. People often use the Quiet Hours to ensure the mini split is not beeping during sleeping hours, nap times, etc...