Mortgage refinancing?

I have been paying my mortgage on time, unfortunately the price of my house dropped dramatically. I asked the company that hold my mortgage to refinance my mortgage from an ARM to a 30 year fixed. After the appraisal, I was told that they could not refinance my mortgage because my house appraised lower than the amount I needed. I have an excellent credit score and no one want to refinance my home. My mortgage is owned by chase and they are telling me that, they can not refinance it because is not a fannie may. What are my options now. Please help because I need to get out of the ARM loan. I will like to know how to get a 30 year mortgage from another lender or from the government (fannie ma)