Pixhawk 4 IO output B/E Led is solid red

Hardware Pixhawk family
1

Hello,
while I was calibrating my Pixhawk 4 Holybro through MissionPlanner, my Pixhawk disconnected with my laptop, the B/E led of IO output is solid red and I can’t connect again to my laptop.
Can you tell me what happened and how to fix it?
Thank you.