Does it climb straight up at all, or does it immediately flip and barely gets off the ground? Instant crash would suggest a weak motor. Does it always flip the same way? Hold it down and fire up the motors and see if one seems under powered. Or have you changed the props recently, the wrong rotation prop would instantly flip the drone. If it does clime straight up before going haywire, try launching with the GPS turned off. There seems to be a common issue with Holy Stone drones and GPS faults that can cause fly-offs.
If you bought it new from Amazon then it may be worth contacting Holy Stone, their customer service is excellent and many people have received replacement drones.