It's common to see a change in your car insurance rates when it's time for policy renewal.
Your insurer takes this opportunity to reassess your risk level by checking various records. They consult with the Department of Motor Vehicles (DMV) to see if you've had any lapses in insurance, received any tickets, or committed any moving violations. Additionally, your insurer will check your credit score; a decline since your last assessment could result in higher premiums.
While some factors are out of your control, like state laws, you can still work on maintaining a good driving record or improving your credit score to lower your future premiums.