
Dear @Viktor Moshkovoy
Thank you so much for contacting Microsoft Q&A Forum.
Based on your description, I understand that you're facing with PowerApps displaying blank lookup columns after publishing, even though it works fine in Studio preview. Therefore, I have tried my best to research in all material documents from Microsoft, but there is no official confirmation for a completed fix with this potential bug.
However, I found these articles during my research that may help you, please kindly take a look to see if they can work:
- Records aren't filtered in lookup for particular entity - Power Apps | Microsoft Learn
- Troubleshoot Lookup issues in model-driven apps - Power Apps | Microsoft Learn
- Filter expression returns extra blank records in results - Power Apps | Microsoft Learn
- Some columns don't contain data in a model-driven app - Power Apps | Microsoft Learn
Also, you can see the discussing in this case (check all comments): SharePoint Lookup Column value not showing
I really want to help you further in this issue. However, as a forum moderator, I have limitations in testing environment and cannot access the internal databases to assist you. So, I highly recommend that you can submit support service for it with Microsoft Support via Contact Us - Developer Support
Or you can go here and choose support section:
App publishing | Microsoft Teams Dev Center
Developer Program | Microsoft 365 Dev Center
I appreciate for your patience and understanding in this matter and I hope your issue can be resolved soon with Microsoft Support. This will allow our dedicated support engineers who have broader diagnostic tools and permissions to investigate and assist you more effectively.
Wish you a pleasant day!
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