revision to gastric bypass
First you need to have a scope to see if there is something physically wrong with the surgery you already have. If that is all fine it usually goes back to revisiting your eating. I would suggest for 2 weeks write down everything you eat and how much just the way you are eating right now. Put it on a site like myfitnesspal and see where the calories are coming from.Then you can see what needs changing to get back on track.
I'm very much in favor of trying to treat regain with diet changes before going on to a revision. You may have already done this I don't know. Once you see exactly what you are eating then go to a good low carb diet, start with something like the Atkins induction for a couple of weeks to detox from carbs and then try to stay under 50-75 carbs a day. Many of us stay under 20 but some find that just too difficult and go by total carbs not net carbs. Try that for month and see how much you lose, if that is working stick with that till you lose the extra weight, sure beats going thru another surgery. Good luck!