I would get your stoma remeasured by a stoma nurse, if you have one. It may be that the holes in your wafers aren't quite the right fit anymore - do your wafers come precut or do you cut out the holes yourselves? I was lazy, so I went for the precut option, but it also meant that the holes were always exactly the same size. However a few months after my operation my stoma had shrunk and a new measurement needed to be done.
It's not the lack of a flat stomach which is a problem. I didn't have a flat belly when I was very underweight, let alone once I put all the weight I had lost back on and then a bit more on top - it all went straight to my belly and breasts. Wafers have to be designed to deal with curves, as most people can't be arsed going down to the gym 6 hours a day to get a flat stomach (although in my case I'm not sure any amount of exercise would work). The hole in the wafer needs to fit around the stoma as closely as possible; the stoma also needs to have a spout and stick out a way.
As I couldn't achieve a perfect fit (my stoma was a slightly weird shape, I think) I had to use barrier seals to fill in the small gap between wafer and stoma. I found the regular Eakin seals too thick though; the slim seals worked better. If you've only tried one brand, it's worth trying one or two others before giving up on barrier seals for good. I didn't get one with one brand, but Eakin and dansac seals were pretty good.
That wasn't quite the end of it unfortunately. The adhesive on my brand of bags started becoming a bit crap and I would get minor leaks after 1-2 days. Switched to coloplast sensura, which finally nailed the leaks problem for good.
Dx Crohn's in June 2000. (Yay )
Tried: 5-ASAs, azathioprine, 6MP, Remicade, methotrexate, Humira, diets.
1st surgery 20/2/13 - subtotal colectomy with end ileostomy.
2nd surgery 10/7/15 - ileorectal anastomosis. Stoma reversed and ileum connected to the rectum.
Current status: Chronic flare. Do I have any other kind?
Current meds: 50mg 6MP