When generating a report on Predefined Case Teams, the Case Number record appears multiple times. This occurs because there are multiple entries for each member within the Predefined Case Teams. These extra rows can lead to unnecessary repetition.
This is working as per the design since the cases are linked to team members based on relationship in the custom report type. The object used in the report type is indeed Case Team Members.
Workaround:
An alternative to accomplish the desired outcome is to create a simple 'Case' report and add cross filter 'Cases with Predefined Case Teams'.
IdeaExchange for this behaviour to upvote - https://ideas.salesforce.com/s/idea/a0B8W00000GdnjkUAB/need-to-ability-to-show-predefined-case-team-name-in-report
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