Bootcamp Partition not showing!

Hello!

I've an iMac 21.5-inch late 2013, with OS X El Capitan Version 10.11.6

Yesterday, i was just working with windows 8,and everything was fine, then turn off the mac and went to bed, today i was holding the option key while turning on the mac just to boot into Macintosh, but i found out my windows partition wasn't there anymore, just MacintoshHD, EFI BOOT and Recovery, then i boot into Macintosh to check what happen, but i can still see my files from bootcamp, still showing on startup disk from the system options panel, and it's also in Disk utility, i select Bootcamp as the primary OS in startup disk, and press restart but when it's on, says "no bootable device", Don't know what to do 😟 , Help!!