Communication system and communication control method to avoid unintended control on multiple communication devices

A communication system, comprising:

• a plurality of communication devices, wherein
• the plurality of communication devices is controlled, by a first external device of a plurality of external devices, in a grouped state,
• the grouped state is a state where the plurality of communication devices is grouped,
• the plurality of communication devices is controlled, by at least one second external device of the plurality of external devices, in an independent state, and
• the independent state is a state where each communication device of the plurality of communication devices is independent of remaining communication devices of the plurality of communication devices, and
• the each communication device of the plurality of communication devices includes:
• a reception unit configured to receive data including a control command and device information from the plurality of external devices,
• a storage unit configured to store the device information regarding the first external device, and
• a control unit configured to:
• determine presence or absence of a cancellation command, wherein the cancellation command corresponds to cancellation of the grouped state;
• and
• control execution of the control command based on the presence or the absence of the cancellation command and the stored device information, wherein
• the stored device information corresponds to information regarding the first external device that has obtained a control right for the grouped state, and
• the control command is included in the data received by the reception unit after the control right for the grouped state is obtained by the first external device.