Hi, I tested the exact same example, with the EF 2.0 database we have in Nexus, and openLCA 1.10.3, and cannot reproduce what you report. Rather:
I create the process, with the two providers
..then create a product system which only links default providers
..and the product system is then linked, as expected, to the two provider processes:
Anything else would also be somehow strange (and not linked to the EF database specifically). So I cannot tell what has happened in your case? Was anything different (other database, openLCA version - although this shouldn't make a difference, maybe you didn't save the process before making the product system, ...)?
Thank you, Andreas