The answer to 'why is my rodent invasion' is that rodent infestations are typically caused by the presence of food, water, and shelter that attracts them to your home. Common signs of a rodent problem include droppings, gnaw marks, noises in the walls or attic, and damage to food packaging or insulation. To solve a rodent issue, you'll need to eliminate their access to food and water sources, seal up entry points, and consider trapping or deterring the pests.
Many rodent problems can be addressed through DIY methods like setting traps, using repellents, and sealing cracks and holes. However, if the infestation is severe or you're unable to fully eliminate the problem, it's best to call in a professional pest control technician. They have the expertise and tools to properly identify the species, locate all access points, and implement a comprehensive treatment plan to get rid of the rodents for good.