Just double checking here:
1. Are you using the right switch on sequence: (a quick press of the power button, release for 1/2 second, then an immediate long press for 3 seconds)
2. Have you removed the charging cable?
Hello there marfig. I am sorry to know that you are having issues with your DJI Mavic Mini and it is great to know that you were able to fix the said issue with the help of our fellow DJI co pilots here at DJI Forum. To power off the said drone kindly please press the power button once , then press again, and hold for two seconds to turn the DJI Mavic Mini off. Have a safe and a happy flying always.