The issue still happen on MacOS Monterey 12.2.1. After getting the pair device from IOBluetoothDevice and tried to open the RFCOMM channel via this API: (IOReturn)openRFCOMMChannelAsync:(IOBluetoothRFCOMMChannel **)rfcommChannel withChannelID:(BluetoothRFCOMMChannelID)channelID delegate:(id)channelDelegate; Then I got these error messages from CoreBluetooth: [CoreBluetooth] WARNING: Unknown error: 431 [CoreBluetooth] WARNING: Unknown error: 910 [CoreBluetooth] Failed to open RFCOMM channel These kind of error messages still also happened: [CoreBluetooth] No name or address [CoreBluetooth] handlePeerDisconnectionCompleted: 64C11C27-7D1A-B3D8-91C7-27B96BC58429 not found It needs a fix from Apple.