I accidentally claimed my daughter as a dependent, even though it was her father's turn. So I need to take her off of my taxes.
Before starting to amend the tax return, wait for the tax refund to be received or the taxes due to be paid and processed by the IRS.
See this TurboTax support FAQ for amending a current year tax return - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-federal-tax-return-current-year/L7eS6o1qh_US_en_US?uid=lfunevhk
Because your daughter's social security number has now been used by IRS, her father will have to file his return by mail. It will be rejected if try to efile.