How to read and write values to the same Data source

In my test I’m using test steps ‘DataSource’ (Excel) and DataSourceLoop’ which will read and iterate ‘usernames’ and ‘passwords’ for a SoapUIPro Load testing.
This works fine.

Now I have a requirement to extract details from test step responses (on the fly ) and write to the same data source (against the usernames and passwords) and use those data as inputs for the test steps at the bottom.

I can extract values from test steps but do NOT know how to write them to the excel data source on the fly. (please note- Same time this excel data source is being read to fetch values for the Load test)