Need cheap car insurance

I pay for my geico car insurance every six months because I save some money instead of paying monthly. Here is a thing I am going to out of US for 3 months and I do not need insure my car however I already paid for the 6 months. Can I cancel my car insurance and get the rest of money back?Do they have any freezing method for these situations? If I cancel my car insurance, will they charge me some money? Will they still provide me cheap car insurance when i come back?