Not ready stays on for 2-3 min. then it shuts off.

Not ready stays on for 2-3 min. then it shuts off.

After I turn on the power button the display shows “not ready”. This stays on for 2-3 minutes while the machine obviously tries to do something and then it shuts off again. I haven’t used the machine for a few years and it was packed back in the box. Now I wanted to use it again and it doesn’t work