Why can I not retrieve data after editing element name and index in Mapper?

Question

I edited the element name and index in Mapper and now I cannot retrieve data.
Where should I check to resolve this problem?

Answer

Please check to make sure that the data exists at the location of the specified index.

If an index is specified, the data is retrieved from the element with the same element name at the specified index.
For example, if there are only three elements named "column" in the input data, even though the data is mapped to be retrieved from the element name "column[6]" in the input schema of Mapper, the value cannot be retrieved and null will be set.

If there are multiple elements with the same name for which no index is specified in the input schema of Mapper, the expected element cannot be identified and the value may be retrieved from another element with the same name.
In this case, please set the index.
　
Edit Schema
https://www.hulft.com/help/en-us/HULFTSquare/Content/Designer/Mapper/mpp_edit_schema.htm