Cigna Healthcare Company has avoided paying my claim for over 6y months now Chattanooga, Tennessee

I am in the process and have been for over six months, of filing a claim for out of network healthcare services. I first submitted the claim in June of 2011.  About a month later I called to check on the status of the claim and Cigna informed me that they were lacking information and the claim had not been accepted. I submitted another claim with the healthcare providers tax I.d. (that is what was requested). Another month passed and Cigna sent me a letter saying they needed the providers facility number? I submitted re-submitted the same info which had the facility number on it and was told that nothing more was required. Another month goes by and I call as usual. The rep tells me that the claim is incomplete and they are missing info, so, I sent the info again and was told the claim was being processed. a MONTH went by and every  time I called I was told the claim was being processed. After two months I called and finally was told that the claim was pending verification and they needed a coy of my birth certificate, D.L., cigna I.D., and SS card. I sent these items in and called a week later to find the claim process was started over again. It is now December 28, 2011. I called today and the rep told me that the claim was listed as a pre-existing condition and was denied. She also told me this was a mistake and she would have to make the changes in the system and re-submit. This has been a nightmare and I caution anyone who thinks of doing business with cigna. They just want me to go away, but I refuse and will continue to fight. I will keep everyone updated on the status of my claim and whether I have decided to seek legal council. They owe me alot of money and are just trying to avoid paying. This is wrong.