I am a nurse and have found many ostomy issues in my career. Do you have a 1 or 2 piece system? I suggest the 2 piece system that comes with a adhesive wafer that attaches to the skin, and a bag that is applied somewhat like the lid of a container, it has a rim and snaps in place. Clean and dry the area around the ileostomy, then I suggest using a sticky skin barrier/prep, apply the wafer then secure all around the edges with a good adhering silk or cloth tape, or if you really want to seal it, you can use a thin duoderm dressing around the edges of the wafer/base.
Go to your local ostomy supply store where they are well trained to help with this. My son endured the same thing....this happens when the surgeons don't consider the correct placement of it. Your medical supply store can help you, we had to take my 16 year old son to one with him holding a towel on his, and they found ways to make it work. I know it's frustrating for you, and I'm sure they can help you. Take care.