Sometimes when i shut Down then the shutdowns takes time and when I open the Os next time it does not o[pen it shows the elementary OS logo and the logo flickers or the some random stuffs which have in brackets OK like this
[OK] some words
then I shutdown by holding power button and then open again .The system boots after some attempts .
Last time when I shutdown I had one node process running and i Just clicked on shutdown icon and then shutdown . But this may not be the case all time .
I had found one answer but it says that the problem is solved in kernel version 4.15.0-42-generic but i am running Linux 4.15.0-47-generic
here is the answer