I would just leave them alone for now. Helping to early will do more harm than good. If it's been over 24 hours and nothing has changed then you can start to take action Plese keep us updated!
What's your humidity currently at? How long have the chicks been internally pipped (since you've been able to hear chirping)?
It can take 24 hours after pipping for them to hatch. Hard as it is, try not to worry too much.