If the supply is TT and you have a normal split load consumer unit with non-RCD protected ways then you need to get a qualified electrician to sort it out ASAP, a fault on a non-RCD circuit can liven up all of the exposed and bonded extraneous conductive parts in the premises and won't disconnect automatically owing to not enough current flowing. This will give you odd readings too, usually something like a L&N reversal.
For what it is worth, volt sticks are excellent for fixing mains xmas tree lights, they are not much use for anything else.
For what it is worth, volt sticks are excellent for fixing mains xmas tree lights, they are not much use for anything else.