Identify last modified by user or date

Situation:

We have a data mapper activity for transformations which were working fine last month, but suddenly we found some changes in mapper showing source attribute is missing without any modifications by any one. Is there any way to track this issue?

Cause:

The error indicates that a target field expected in the mapping does not exist. This would mean that the target schema has been updated and the node /Root/Record/Org_materialID no longer exists

Tip:

If you have version control enabled, you can refer to the version control system to identify any possible changes in the mapping or target schema.

If not, you can try to identify the change using the last modified date of the target schema (Right click on the schema > View). You will then see the Last Modified Date and Last Modified By attributes.