My phone model is Xiaomi Poco M3. A few days ago, it wouldn't charge. I took it to the service center. They fixed it. But after I switch off the phone, it doesn't turn on. I tried to hold the power button long time, still it doesn't work. I again went to the service center, and they fixed it. I switched off the phone and restarted it. It works well. But after returning home, I used the phone and switched it off, and went to sleep. In the morning, it still doesn't turn on.
It seems like the phone doesn't turn on when it is switched off for long hours. How can I fix it?