Manage the ambiguity problem between 2 tables

Hi Everybody, 

I'm Melvin, i'm a beginer in Power BI. 🙂

I'm trying to connect some tables, but i have a problem with ambiguity in the relationships.

I would like to connect one table of data (USER) to a the main table, with two relationships :

- USER to AUDITOR

- USER to PARTICIPANT

Both of Auditor and Participant use the same User table. 

I Create an example to illustrate my problem : 

I have an "audits" table that uses 2 differents databases to fill 3 data field.
I can connect my "clients" database with the "clients_id" field of the "audits" table but I can't connect user_id with participant and user_id with auditor simultaneously. 

How can I connect 2 field of my AUDIT  table to the USER table ? 

I watch some tutos about this subject but i don't understand how to manage this problem. 

Thanks a lot for yout Help 😉