Thanks for the reply. I've done three resets so far with no luck.
Three resets... As in just rebooting the device?
Or did you actually perform 3 factory resets (which means all data is wiped and restores device to factory settings)?
Before doing a factory reset, make sure all important data is backed up as this will wipe all data on the device.
There are 2 ways to factory reset your device.
First method (within device settings):
Go into Settings>Back up and reset>Factory data reset
Second method (Android Recovery Console; the method I prefer and suggest):
1) press and hold the Volume Up and Power buttons together at the same time.
2) wait for the device to boot to the Note 10.1 logo and only let go of the Power button
3) when you see the green android on your screen, let go of the Volume Up button
4) it should now be booting to the Android Recovery Console
5) use the volume +/- buttons to navigate the menu
6) scroll to 'wipe data/factory reset' and press the power button
7) scroll to 'Yes -- delete all user data' and press the power button
8) it will wipe/restore partitions
9) when completed, select 'reboot system now'.
A factory reset (in most cases) will fix any issues experienced.
If it did not fix the issue and you still experience incorrect battery readings, then the sensor is likely faulty and you should get the Note 10.1 exchanged.