Can I sue Farmers Insurance Exchange

I originally commented about my insurance agent, Farmers Insurance, charging me $215 a month for my teen when he had his learners permit and I he was learning how to drive in my car. I found out from others that they did not have to pay any additional premiums for their teens when they were learning to drive. Since I posted this I did some research and found out that many insurance companies do not charge additional insurance for someone with a learners permit. State Farm, Allstate, Esurance to name a few. The I emailed 40 Farmers Ins Agents and more than half said that Farmers does not charge additional premium for drivers until they get license. I contacted my Farmers agent and demanded that he return the $2,100 that I paid to have my son insured while he had his permit. My agent said he would forward my request to underwriting. After a week I had not heard back from my agent so I contacted him again. He said he had not heard anything yet. Another week went by and still I had not heard from my agent. I was planning on calling my agent again to find out if he had heard anything from underwriting but I got so busy at work that I didn't have time to call him. To my surprise when I got home a check, in the amount of $1,972, from Farmers Ins was waiting for me. There was a letter with the check that just said that the check was being issued due to an overpayment.

The insurance agent that provides life insurance for all the employees where I work told me that I should have sued them. She said that insurance companies don't usually like to refund money and that this is their way of not having to admit that they did anything wrong or unethical.

My question is: can I sue them? Does anyone know where I might find information pertaining to this issue? Or a lawyer that I might ask?