How to fix flash on a nikon D3000?

I recently droped my Nikon D3000.it fell off a chair i thought it had hit the lens but the flash hit the ground. It was unable to pop up automatically. I played around with it and now it does pop up.but, the flash no longer works.

There's nothing you can do with the flash, you need to send it back to Nikon for repair. Or get an external flash and use that instead, which would probably be cheaper.

You've got several option

Option A: Send the camera in for repairs.

Option B: Learn how to use the camera without the use of the flash.

Option C: Purchase an external flash.

A pop up flash is not worth repairing unless it's being done for free. You'll get much better results from an external flash. They're higher so less shadows from the lens and they put out more light. Pop up flashes are next to worthless and mostly a gimmick for the entry level set.