drive failure maybe
 

put floppy in the amiga and light come on about 3 secs and goes back to main could be drive falauire its amiga a600

Does it sound like the disk is spinning? Could be drive failure, could be a machine or cable fault. Could be as simple as dirty disk heads. Are you sure the disk works? Try a head cleaner disk if you can.

i tried an orginal game and workbench disk and same issue so might defo be the drive

From my side I managed to save a couple of floppy drives through a good cleanup using isopropyl alcohol + cotton bulbs. Try to remove as much dust as possible and also cleaning the heads.