Bootcamp disappeared

Hi, I used to have windows installed on bootcamp partition, but it has suddenly disappeared from my finder as well as when I restart to select the os. I have a lot of important data on the windows partition if someone could please help recovering or getting access to bootcamp partition. From what I remember the last thing i did was to download the windows support software onto a usb drive using the online instructions which stated.

Download the Windows support software

After preparing your USB flash drive, complete these steps:

1. Make sure that your Mac is connected to the Internet.
2. Open Boot Camp Assistant, which is in the Utilities folder of your Applications folder.
3. From the menu bar at the top of your screen, choose Action > Download Windows Support Software, then choose your USB flash drive as the save destination. When the download completes, quit Boot Camp Assistant.