When adding, you can create an input field by copying the last entered value.
"Contents" of the repeated container "negotiation history" is set to copy at the time of addition.
In Figure 1, when you press the add button, the copied value (in the previous line) is set to "contents" as shown in Figure 2.
Prepare a repeating container 'negotiation history'.(Figure 3)
You set the details of the repeating container type item ("Breakdown" item in this example).
Check "Copy values on addition" in the repeat setting on the input control tab of model item detail definition.