Already had gastric by-pass in 2002 & surgeon wants to revise :-(

I had gastric by pass in 2002 and lost 100 pounds. It's been almost three years, the weight loss has stopped and I have developed a constant belching problem. After an EGD, my surgeon suggested doing a revision to my revision-make the top of pouch smaller and the bottom portion bigger. Hopefully cure the belching and begin weight loss again. My problem-Insurnace denied-stating no medical reasons for revision. I have written letters from my suregon, PCP, CEO of my hospital and myself. Waiting on anwser after filing a greviance. Has anyone had to have a second revision? Why? How did you get it paid for? Help me PLEASE!