This isn't meant to sound blunt, but there in lies your answer. You try to eat the right things but cannot stick to it - if you can't then it won't work.
We've suggested to you on other threads things to try, changes that you can implement in terms of changing protein and carb levels - you've never said whether you've tried any of them. But, the band is only a tool to aid weight loss, it isn't the answer, it's not working for you because as you say, you're not working with it in terms of what you are eating.
The answer comes in US making the changes to make the band work, not from the band itself. And if you're not able to continue to make those changes then the band won't work, except its not the band that isn't working, it's you that isn't working with the band.
It isn't an easy option and maybe you weren't given the proper advice with regards to your eating before having a band fitted. But you need to make THG listen. You need to get them to review your fills, make sure that they are working to find restriction and working with you and the foods that you eat.
Unfortunately, it isn't a quick fix. I'm 16 months post band op next week and I still do not have restriction from my band, but I follow the guidelines because even without that and even with constant hunger I am determined to make it work.
Go back to THG, make them listen. But you have to be prepared to make the changes to your eating, to the foods you eat, because otherwise you will never get the results that you're looking for.