It depends on where you purchased the keys from. If you purchased from another member of MPGH, odds are that the key is already in circulation of possibly hundreds of other users, and at least 90% would be using the keys for hacking. Just about any key purchased through another member will last a week AT MOST, and that would be incredibly rare. If you purchased off of steam, your key will most likely not get banned spontaneously, however, if you have ever tried hacking (even once) or using things such as Dayz Navigator, you could easily have been banned for that as well.