Carry Forward value within nested repeats

**1. What is the issue? Please be detailed.
**
I am trying to make a value carry forward for some fields within a nested repeat without success. For example;
session is the outer repeat, and observation is the inner repeat. In a given day, there are many sessions and each session can have many observations. Most observations will have some field values be the same, and i want that value to carry forward between observations within a session and across all sessions.
I’ve looked at the documentation and forums and havent been able to get this to work. Any advice would be appreciated!

2. What steps can we take to reproduce this issue?

3. What have you tried to fix the issue?

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