I had that happen to me once....the fold was a bit too deep to be "quilted out." What I did was fold it over and quilted the heck out of it, It helped the print was very busy, and it didn't matter. In your case, it appears you are tying the quilt, right? What you can do is whipstich over the folded edge with tiny, tiny stitches. Or you can fold it down and applique something pretty over it and repeat the applique in a few more places so that it looks done on purpose. Good luck!