Refresh times out on tiny data set

I have a particular dataset that connects to a postgres database that I also manage. Other reports that connect to this same database via our On-Premises Gateway work fine.

This dataset, which is less than 200,000 rows (about 7.5 MB), times out before it can refresh on Service. It refreshes in less than 1 minute on Desktop. I can also see that refreshing on PowerBI service is successfully connecting to the database, but it seems like Service isn't actually pulling the data. The connections sit idle on the postgres side. In contrast, when refreshing on Desktop, the postgres server shows the connections and shows data flowing to PowerBI and everything works as expected.

I have tried:

• Deleting the report from Service, clearing the cache on Desktop, and re-uploading.
• Minimizing the dataset size (I could get it even smaller, but I don't think that's the issue)
• Minimizing the PowerQuery steps for the report. There are only some column type changes.

Why does Service time out? Is there something I have missed?