Assuming you’re using the barrier cream correctly (*after* each BM) then it’s way past time to try some other things. The easiest thing to try is tinkering with the pH, using something like Zantac, Prilosec, or even Tums. You’ll know pretty soon if it helps. Another thing worth trying is cholestyramine resin, but that needs a prescription. Has you GI (or surgeon) taken a look? It’s hard to inspect ourselves down there.