Cube orange neither booting nor connecting to pc

Hlo there I have been flying arducopter 4.1.3 using Cube orange past 2 month
now i had little work to do so I almost didnt fly it about 1 month.After that I again wanted to fly so I connected to pc and it didn’t boot or connect to the pc
But when I unscrew the carrier board along with the main cube and reconnected again started to work I just wanted to know why did it behave so and why is it working now

Did you separate the Cube from carrier board before?
Did you hear a clear “click” sound when plugging the Cube into the carrier board?
When you tried to boot the Cube, how did you power it?

yes i did no i didnt clearly listened click sound i power up using usb

Did the status lights come on?

Previously when there was problem the light was always on but when it’s working now at startup light comes on and after it goes out but it’s working.