Where did you see $4000?  All of the child-related credits are affected in a big way by the amount of income you earned by working.  Have you entered all of the income you received in 2019?  When you entered information about your child in My Info did you say he lived with you the whole year?  You have to say that for a newborn.  Without any personal information, could you tell us what is in box 1 of your W-2?

I don’t get my child credit 

As long as you haven't submitted payment, deducted the TurboTax fee from your refund, or registered, you can erase your return and start from scratch in TurboTax Online. Please click the TurboTax Help link, listed below, to learn how to clear and start over. 

https://ttlc.intuit.com/questions/2586254-how-do-i-clear-and-start-over-in-turbotax-online

The refund amount changing could mean that the IRS or your state adjusted your return based on information that they had that is different than what you reported. Generally, the state or the IRS will send a letter notifying you of the changes. 

Please click the link below to learn why the TurboTax meter may have changed. 

https://ttlc.intuit.com/community/troubleshooting/help/why-did-the-turbotax-refund-meter-change-afte...