Hi Sachin,

The main issue is that you want to link data from the NPG_EM_custom table with the _CEL_EM_LINE_iExpense table, but Celonis cannot find a clear connection between both tables where each row can be linked to only one other row of the linked table.

This is caused since the table in the middle (your case table) have multiple linked rows on both the left and right hand side. Therefore, each row in the NPG_EM_custom table can refer to multiple rows in the _CEL_EM_LINE_iExpense table, something what Celonis doesn't allow (or you should use aggregations such as SUM, AVG, MIN, MAX etc.)

In the documentation (link), you can find more information about this topic, and learn what is meant by a common table.

Also, a workaround for this is presented in a earlier asked question: I would like to connect two fields that have an indirect N:N relation. Is this something which I can do via a PU_Function? (celopeers.com)

Hope this will help.

Kind regards,

Jan-peter