Hi @ck01,

Welcome to the community.
The answer to this question will depend on where the data is stored.
If it's in a Table, please see the video in the table help file, which demonstrates how to select a cost center and display a cost center code.
If you are using external data, the same concepts can be applied.
https://help.nintex.com/en-US/nwc/Content/Dashboard/Tables.htm

Hi @ck01 
Have you solved your question? 

hi not yet

i found the below video however its not based on forms. so im still not sure how to look up a table set up in nintex when the user input is included in the repeating section. 

Create a dynamic repeating section | Community

Hi ​@ck01 

Sorry, am I missing something?  The video is entirely based on forms/
Yes, it's for O365, but the concepts are the same.

hi Simon

The video refers to updating rows based on data collected via a start event form. I need the look up to take place in the start event form itself. I have set up a repeating section with the material code as a drop-down list based on data table. Once the material code is selected, i would like the Repl. val to be dynamic based on the data table.  Is it possible within the repeating section? 

thanks