FAT-fs (sda2): Volume was not properly unmounted

[janeku]

Good morning,
My daughter has powered off Pine directly from power supply without shut down procedure. 
Any thoughts how to fix it ?

This is what I got when ran dmesg:

[   65.856602] FAT-fs (sda2): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.

When I run fsck I get back:

e2fsck 1.43 (17-May-2016)
/dev/mmcblk0p2 is mounted.
e2fsck: Cannot continue, aborting.

How to fix this ?

Regards,