Samsung S7 unresponsive with blue light slightly pulsing

My Samsung Galaxy S7 is completely unresponsive for day and a half, black screen, only blue LED is shining with a slight pulse. According to [this guide](https://www.samsung.com/uk/support/mobile-devices/what-do-the-notification-light-colours-mean-on-my-samsung-galaxy-smartphone/) , it means "the device is turning on or off". For a day and a half already! So I tried this advice: > Press and hold the “Power” and “Volume Down” > buttons for eight to twenty seconds and the device will eventually > turn off. Then I tried [this advice](https://forums.androidcentral.com/ask-question/992633-galaxy-s7-wont-turn-wont-force-restart-blue-led-solid.html) : > Try pressing and holding Power and Vol Down for about 30 seconds, then > wait a few seconds, then press and hold Power again for another 30 > seconds. Then I tried different sequences [as advised here](https://www.youtube.com/watch?v=LP4sD3AAWEA) : > up+power 20 secs > down+power+home > up+power+home Nothing worked. Charging didn't help. Before this happened, my phone was gradually slower and slower in the last month, until it became super slow, as I [asked here](https://android.stackexchange.com/questions/247038/what-to-do-when-phone-is-super-slow) . Some time before the freeze happened, I also removed the SIM card and micro SD card from the tray. Now I put back the SIM card, the system still stuck. PS: 10 minutes after the key combo attempts I noticed the battery and display is heated. Interesting. PS: after 2.5 days the battery finally died and the blue light stopped pulsing. I charged it a little, but now it doesn't even turn on. No response whatsoever.