Mac does not completely shut down when battery runs out

Hi everyone!

I have macbook pro 15” 2018 with touchbar, Mojave.

My macbook switched off when battery ran out (0%). However, i realized it not completely turned off. When i touched keyboard, the screen and touchbar displayed but just flashed in 1 second. This phenomenon repeated 3-4 times then my macbook completely turned off. I think my macbook still has battery remaining but i don’t know why it switched off?

Can anyone explain to me?

Thanks and best regard!