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Hi,tomerbi I am glad to help you.
Hello,mh2587 thanks for your concern about this issue.

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

You can try to use dataflow as data source for data joining to create a report
Since you mentioned that your data is executing fine in Power query and it takes less time. So you can consider to create a dataflow with the same function as the original data source, and use the dataflow as the new data source for data fetching. At the same time, the report using the dataflow as a data source does not need to create a gateway connection to its semantic model on the services. You just need to create a schedule refresh for the dataflow separately. This bypasses the usual gateway connection configuration.
Dataflow can be thought of as a power query on the cloud service. If your report data is processed correctly in the power query, it should be processed correctly in the data stream.

On this basis, you can try to optimize your data structure, avoid too complex relationship structure, if possible, please reduce some unnecessary data, so as to reduce the burden.
I hope you find the following documentation helpful:
URL:Creating a dataflow - Power BI | Microsoft Learn

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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