Insurance companies are in business, primarily, to make money. When a customer files multiple claims within a certain time frame (usually 3 years), this begins to cost the insurance company more money than they are receiving from that customer. While not every company will non-renew your policy for multiple claims, there are many that will consider 3 or more claims within a 3 year window as excessive, and thus too expensive to insure. You should be able to find a new policy with a different provider since they aren't having to cover your previous claims, but keep in mind that more claims can put you back in the same situation. Compare quotes
with as many companies as possible to find the best rate.