Hi Pouyan,
Unfortunately, you can't do this without changing the source of the form manually, changing the <xf:itemset> element to get the values from something that was filled in the form previously, e.g.:
<xf:itemset ref="/form/children/child/child-iteration/first-name">
<xf:label ref="."/>
<xf:value ref="."/>
</xf:itemset>
See a full example that you can paste in Form Builder to test this out:
https://gist.github.com/avernet/6fe0fead6ac77e980a76Alex
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