Scanning is stopped after timeout. But the BLE device is alive for sure - Chrome-browser easily continue connecting and disconnecting from this BLE device (based on ESP32 module), and reading a GATT characteristic is OK also any time after connect.
But if to use the Airplane Mode for a second on the Android13 (device is in my post footer) - again B4A app scans and connects OK. Again only once.
Looks like BLEmanager2 lib does not disconnect well...
Example project is attached: it's just combined BLEexample and Bluetooth example (with selecting devices from the list).
Please, just try to connect to your BLE-device, disconnect (after successfull connection) - and connect again.
I see now that error is ... second connection just does not work (disconnected in several seconds), until re-powering the BLE module (airplane mode for a second):