If you have both filed your tax returns and both of you claimed your daughter as a dependent, you will have to wait until the tax return is accepted by the IRS.
It is possible the return(s) will be rejected. If that happens, you can correct the return once you receive the rejection code to ensure only one of you claims your daughter.
If both returns are accepted, one of you will need to file an amended tax return to correct the dependent being claimed twice.
Attached are instructions for amending returns:
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