I had a b16a n EF swap done on my EG abt 1 year ago and 5 months ago i saw oil mixed with water . So i found out my block warped so i had the engine rebuilt. Now I have my car back and there's still oil mixed with the water. I know the problem for this is usually the gasket. Except we already changed the gasket.
What could this be?

 

A crack in the block would cause this.