My house alarm keeps going off, how do I stop it?

My house alarm has gone off twice now in the past few months. There is no one trying to enter it, the battery was just replaced about a year ago (I heard they last about 5 years). I don’t know who the original installinig company was so can I call any random alarm company? How do I get it to stop? The sign that shows up is “bypass”…oh and it wasn’t armed both times that it’s gone off