Not able to schedule automatic refresh in service.

Hi asdf1608 ,

If your data source is On-premises SQL Server, you need install gateway firstly.

Please try below steps:

1. Download the latested gateway, install and configure

2. Create a datasource in Power BI Service for SQL Server

3. Open dataset, under the "Gateway  connection" tab, select the gateway and map the data source

4. Create the schedule refresh policy

For more details, you can read related document: 

1. Download and install the gateway on a local computer.
2. Configure the gateway based on your firewall and other network requirements.
3. Add gateway admins who can also manage and administer other network requirements.
4. Troubleshoot the gateway if there are errors.
5. Add or remove a gateway data source - Power BI | Microsoft Learn
6. Manage your data source - SQL - Power BI | Microsoft Learn

Best regards,
Community Support Team_Binbin Yu
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