Cannot copy from on prem to Fabric SQL Database

I created the connection, it tests correctly, I can see the database in the destination and select the table. But when I run it I get an error (server and database xxxx'd out by me).

ErrorCode=SqlFailedToConnect,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Cannot connect to SQL Database. Please contact SQL server team for further support. Server: '[xxxxxxxxxx]', Database: '[xxxxxxxxx]', User: ''. Check the connection configuration is correct, and make sure the SQL Database firewall allows the Data Factory runtime to access.,Source=Microsoft.DataTransfer.ClientLibrary,''Type=System.Data.SqlClient.SqlException,Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server),Source=.Net SqlClient Data Provider,SqlErrorNumber=53,Class=20,ErrorCode=-2146232060,State=0,Errors=[{Class=20,Number=53,State=0,Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server),},],''Type=System.ComponentModel.Win32Exception,Message=The network path was not found,Source=,'