Bluepy Ble disconnect when using bluetoothctl scan on

hi, i use bluepy library to connect a ble device to get some data,

and im sure my raspberry pi ble connection parameters match that device(conn_max_interval, conn_min_interval...etc),

it working perfect!

but when i use terminal open bluetoothctl and write command "scan on" to find some classic bluetooth devices,

after bluetoothctl scan device,

my ble connection disconnected,

is there anyone have same problem with me??

details info as below:

IanHarvey / bluepy