CoachS_2010

I am having trouble with my iPhone 6 geocaching app compass. It tells me I'm within a couple feet from a cache but then it shoots to a longer distance the other direction. (I.e. say I'm within 3 ft. North and then it changes to 27 ft. West.) How can I improve the accuracy of my compass? I haven't played in several years but I don't remember the accuracy being this off. Thanks!