The reason that the compass is not showing north is most likely due to it being subjected to a magnetic field that has polarized the needle. This is, unfortunately, fairly common in today’s world since we carry a lot of items that emit a magnetic field such as mobile phones, GPS and other equipment. A compass needle cannot change its own polarization; it has to be “forced” to reverse its polarity by a magnetic field.
We write in the manual that it is very important to check the compass every time it is used since polarizations does happen, it is as important as checking any part of your survival gear before it is used, since your life may very well depend on its functions.
It is not complicated to reverse the polarization of the needle but to be 100% sure of the result you should be using a controlled magnetic field. Because of this we do not recommend that you polarize your compass by yourself.