first of all, check your powercable to the floppy drive, secondly check if the floppycable is correctly seated...
if the above don't work, check the BIOS setting if the device is actuated...
if all the above are correctly done/checked and it still doesn't function... go buy a new floppy drive if you really need to have one... they should be around $10 US or 10 €...
Ben