@Felthry need more info: what do you mean by "doesn't exist anymore" ? Can you turn it on in the Windows settings? (I'm assuming you use Windows)
My course of action would be to check in the device manager if the Bluetooth adapter is still there, not disabled, marked as connected
I would also look for a physical switch on your computer that might turn it on or off
If all else fails I would attempt reinstalling the adapter's drivers
@Felthry I would attempt reinstalling the driver then
If you don't know where to look, I'd look up your laptop (I assume it's a laptop or otherwise a prebuilt desktop) model on the manufacturer's support website, you should find it in the drivers category