RelationShip field is always empty

Hi,HotChilli ,thanks for your concern about this issue.

Your answer is excellent!
And I would like to share some additional solutions below.

Hello,mvcsharepointde .I am glad to help you.

You may need to check in Power BI Desktop that the field that was accidentally shown as null is real data, I suggest you to manually filter in the direction of the relationship, if your data connection mode is not import mode, please check if the data is real data in your data source.
If you can really guarantee that the data really exists, please try to change the direction of one-to-many filtering to unidirectional filtering (from one to *).
Sometimes two-way filtering may lead to unexpected cross-filtering, affecting the completeness and accuracy of the data.
Can you provide a screenshot of a relevant pbix file that does not contain sensitive data, which would help to resolve your issue?

I hope the following checkissue on data is helpful.
URL:
Solved: Relationship query - Microsoft Fabric Community

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Carson Jian,
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