Why is it so hard to maintain the weight after a sleeve gastrectomy? I have gained some weight back. Not happy about it.

Maintain your diet. if you do not stay on special diet there is no surgery on earth is going to make you lose weight while you are eating whatever you want surgery supposed to be a tool for a new fresh start not a goal .that why every patient should go through a psychiatric avaluation before surgery enjoy the weight you lost and stick to a diet to maintain what you lost there is no free ride or magic trick.