You think the issue is gone, and then they suddenly come back after some time. There are wide ranging different types of mole traps available that could be use to catch moles in a humane fashion, so you can catch and release them without killing them. https://wiki.insidertoday.org/index.php/Reasons_For_Hiring_A_Pest_Control_Company_For_Your_Treatment_Of_Domestic_Pests