Hi, I’m sewing a wrap dress with a satin-like very slippery fabric. I’m having some problems with the hem, which is by the way on a curved edge. At first I tried sewing it with a rolled hem foot, but it came out uneven and kinda ruched. I than tried to roll it over one more time to make it smoother, and it worked, but the hem keeps rolling over and it’s visible from the right side of the dress. What did I do wrong? What can I do to fix it?