No Bootable Device Problem

I currently have an Acer Swift 3 SF315-52 Laptop. I restarted the computer to fix an application bug, but when I tried to boot it up, it gave me a “No Bootable Device” Error. I looked into possible fix’s on the internet and most of them recommend changing the Boot Mode from UEFI to Legacy. However, this option is grayed out for me and I cannot change it. I have attempted to change many other settings in the bios to change the boot mode, but I have still not figured it out. Does anybody know how to fix this?