If you have the Raw file use the Highlights slider in Camera Raw. If not then you can use the same in the Camera Raw filter but it will not be as effective.
If the above suggestions don't work - Blown out highlights have no data in them - these aren't completely white, but brining back detail doesn't work very well if at all in white areas. You can use some of the healing tools, clone stamp to try and add a little color in there - set it to darken.
Took me a minute to learn the healing and clone stamp tools but they did the trick. Thank you!