Can't find a bra that fits?

I measure 26 around my ribcage and approximately 29/30 around my bust. I've been wearing a 32A, which doesn't fit at all. The cup sort of fits, but the band is way too big. I was told that I'm a 28C/28D based off of my measurements so I tried a 28C and a 28D in the Royce brand. The 28C fit, but the shape wasn't right for me, so I had to send it back. I tried a 28C/28D in the Panache, Pour Moi, and Freya brands but they were huge and they don't carry 28B or 28A for me to try. I got a 28A from The Little Bra Company, but it was too small. I didn't bother ordering the next size up to try because the fabric is too flimsy. What size am I? Where can I find a bra in my size?